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This is a small review of my Acer TimelineX 4820TG that I purchased a few days ago. Now, I won’t be talking numbers (like CPU/GPU performance etc) because these things are almost same as per the component used and have been covered in various other reviews online. What I’ll concentrate more upon are the things that other reviewers don’t look at, or look at purely from numbers perspective which don’t make sense to an average buyer. Please let me know if I miss something out that you want to know about this laptop.

For clarification, I bought the topmost model of the TimelineX 14 incher series which has a core i5 430m with ATi 5650 1 GB graphics. (Other models have i3 only and one has 512mb graphics, while lowest end has only intel HD graphics). I bought it from Croma Retail for a price of 45,999 INR. So, here it goes:

Frame/Overall Build Quality: Overall, TimelineX 4820TG “feels” sturdy. It has a brushed metal lid and a plastic bottom. There is some flex all around, especially in the lid area but that is to be expected from a laptop which is so thin. For reference, I compared it to a lot of other laptops with almost similar dimensions, and the build quality and flex was generally on par with all of them, except the Asus Bamboo series and macbooks. I wouldn’t worry too much about it though. It is perfectly luggable through the campus or office, just that I wouldn’t keep anything heavy on top of it (I used to keep a lot of my books and other stuff on top of my previous laptop).

Keyboard: 4820TG’s keyboard is chiclet-type but it feels a bit flimsy as compared to the competition. It seems that the keys do not have support all arund but just at the center, so you can see the key edges tilting while typing. Also, the keys are not beveled but flat, which could put off few users though it was not a hindrance for me. Also, the keys feel just a tad bit mushy. But it takes just a few hours to get used to it. Only thing I’m not sure is whether I’ll still feel the same about this keyboard one year from now.

Touchpad: The touchpad is awesome. It is fairly big compared to what others give you these days. It is also multi-touch and supports the usual gestures like two fingure scroll, pinch-zoom, rotate, etc and I guess you could extend these pretty easily by using appropriate software. The click buttons are rocker-type, i.e., a single bar serves as the two buttons depending on where you press. It’s ok but you have to be slightly more careful than having two separate buttons here as you have to press near the ends for the clicks to register properly. Though this also becomes a second nature after a few hours of use.

Weight: The notebook is very light. I haven’t measured it on a weighing scale but for the oomph it packs, it is pretty slim and light. I can lift it easily by two fingers without feeling any strain and can work for hours with it sitting on my lap.

Heat / Temperature / Noise: The heat and noise emission is very low. While browsing and downloading and doing other general stuff, I couldn hardly feel it heating up while on my laps. The left top area on the underside (just near the vents) becomes a bit warm after prolonged use but still it is not unconfortable. The keyboard and wrist/palm rest areas remain cool throughout. I could not hear the fans at all while doing normal work in the dead of night and this turns into a slight whirr when the laptop is tasked with heavier crunching.

Battery Life: This is the USP of this model and one of the biggest reason why I went for it. This laptop has switchable graphics, i.e., you can chose to use the onboard intel GMA HD graphics for regular use or multimedia playback (plays HD media beautifully) or switch to the ATi 5650 for heavier tasks like gaming, etc. While using the intel graphics, I could easily browse for around 5 hours. I also downloaded around 500mb of stuff during this time and another 300 mb worth of windows updates were downloaded and installed. Moreover, this was all on normal settings and that too when I had a very poor wi-fi signal. I hadn’t mucked around with any power saving options at all and I believe that doing that, along with dimming the brightness and better wi-fi signal etc would easily pump it over the 6 hour mark. This is not as much as the 8 hours that Acer promises but still, it is excellent and much better than most of the competition. While turning on ATi 5650 for the same type of tasks reduced the battery life to around 3 hours.

Performance: I didn’t run any benchmarks on the laptop and neither did I do any gaming, but I didn’t feel any slow downs while doing any normal tasks and 720p/1080p media playback even while using the intel graphics.

This is it for now. I’ll keep updating it as more things come to my mind. I hope I have touched upon the significant aspects that I found missing when I was searching around for reviews of this laptop. Let me know if you have any queries for it and I’ll surely update it. Also, I haven’t gone into too much details as I’m primarily a linux user and haven’t explored or tasked this laptop too much till now. I’ll also be installing Ubuntu Maverick Meerkat on this asap and blog about this laptop’s linux compatibility, issues, fixes and workarounds as well.

© Shantanu Goel | Acer TimelineX 4820TG Mini-Review

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There has been a spate of security reports recently about Android apps being malware or suspicious. Most of these were found baseless but at least one was indeed correct (e.g. The Russian Trojan app). We also know that Android has a very good security model but even then, the rest of the reports also makes one think and focus on why an apps requires the permissions that it states it needs?

We all MUST check the permissions that an app requires before installing it and then contemplate what particular feature of the app would require any mentioned permission. The problem here is two part. First is that the permissions can be cryptic. Now, I can understand most of these as I also develop Android apps but I’d fathom that a huge majority wouldn’t. A simple solution to this would be for Google to provide more details (and probably examples) for each permission. One can say that it is difficult and a UI nightmare to include too much of text into the limited space that the mobile screen gets. My suggestion here would be to keep the existing layout as it is, but when someone clicks on a requested permission, he be taken to a new page which describes the permission in detailed but simple words and also provides examples.

But this is just the first part of the current problem. The more important issue most apps are facing these days is “permission creep in“, i.e., they request for permissions they don’t really require. This could be because either they are just adding it to their manifest file mistakenly without using them or are taking a long route for solving a problem that should ideally have been solved in a much easier way without requiring excessive permissions. This permission creep in makes even legit apps look bad. e.g. There was this recent case of a wallpaper app which was crucified by mainstream media all over the world because of the permissions it was using and then it turned out to be just that the developer’s method to solve a particular problem (providing “favorites” and “recommended” features to users) was long-winded.This is quite common today in Android marketplace. e.g. I tried to install the hugely famous “Chomp SMS” app today and noticed that it requires my “location” as well. Pretty weird that an SMS app needs my location and when combined with the “Internet” permission that it requires as well, it made me go “hmmm” even though it is tried and tested by a huge number of people without issues. Then I realized that it might need the internet permission for ads (since I was downloading the free version) but still a bit doubtful about location, probably that is needed for ads targeting (especially because it wanted my coarse location only, i.e., cell-triangulation location by which it can easily identify my general region or country, which is all what is needed) but I’m still not sure. Even the Android Guru Mark Murphy has similar reservations about another popular app Evernote.

The solution? I think Google should make it mandatory for app publishers to explain in the market that why their app needs each of the permissions it requests. This should be concisely explained to the user before installation and then the user-review feature of Android marketplace can take over to determine whether the explanation given is indeed satisfactory enough or not. This would, e.g., make it immediately clear to any potential Chomp SMS users why it needs the location. I’m sure this would lead to even more sales for the good and trusted apps as people like me who were skeptical of something can put their doubts to rest. At the same time, it would quickly push the russian trojan like apps down into the oblivion.

A side effect/benefit of this approach will also be that the app authors would look at the permissions that they use more cautiously and would probably try to weed out the unnecessary ones.

Another idea that I have in mind is more community based. I’m not sure if Google will implement the above idea or even if they do, would they make it mandatory since market already has almost a 100,000 apps without this info. BUT, if someone can take up the mantle of making a community site that documents, with the help of android users, the potential uses of all apps’ permissions and also raise flags on any app having a permission without any apparent need, this would become a boon to the Android users. AppBrain, are you listening? I think this would be a good addition to your already excellent service.

What are your ideas about solving the apps and permissions problems and removing the malware scare that looms upon us? Let me know in the comments..

© Shantanu Goel | Solving The Android Permissions And Malware Puzzle

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Many Android Developers (and users) get confused that why a certain app isn’t showing up on the new Xperia X10 Mini (and few other) phones. This happens even if they support all android versions and have published their apps for all countries, so that shouldn’t be the issue. I came across this as well when few people mentioned that they couldn’t find my app Wi-Fi Keep Alive in the X10 mini marketplace. On some digging into the android docs and the X10 mini specs, I found the issue.

The problem is that the X10 mini has a very small screen with only a QVGA resolution. This screen size/resolution wasn’t supported by Android until recently and the Android system might not be able to scale resources and layouts designed for other screen sizes well enough to suit the X10 mini. Hence, the Android system designers have chosen that any app which does not declare explicit support for small screens (i.e., the app dev has tested his app on small screens and made any changes, if needed, and then declared that everything works fine in the Android Manifest) then it is considered not compatible by default and hence, the Android marketplace will filter your app out.

Now, this is a big loss. A lot of X10 minis were sold and there are lot of new low-tier and cheap Android smartphones coming out with this resolution, so it is a significant market share that you can’t afford to lose. The solution is simple. If the app does indeed work fine on small screens (or you have fixed it to work), then all you got to do is add the below mentioned line in your AndroidManifest.xml:

<supports-screens android:smallScreens=”true” />

That’s it. Your app should now show up fine in all screen sizes markets. Note that for all other screen sizes and resolutions, Android considers the default support as true and your app will show in those markets even if you don’t make any explicit declarations for them. You can read more about this here: Supporting Multiple Screens in Android

Update: Blundell pointed out in the comments that Android documentation says

If android:minSdkVersion or android:targetSdkVersion is “4″ (Android 1.6) or higher, the default value for everything is true. If your application requires Android 1.6 features, but does not support these densities and/or screen sizes, you need to set the appropriate attributes to false.

This should mean that small screens should be set as supported by default if you have your minSdk or targetSdk  set to anything above or equal to 4. However, in my case, my apps had minSdk as 3 but targetSdk as 7 or 8 but still they didn’t show up in X10 mini marketplace till I added the smallScreens support to true in my manifest file. If anyone has any ideas about as to why it was like this, please let me know.

© Shantanu Goel | Android Dev Tip: App Not Showing on X10 Mini Marketplace

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If you want to have a secure browsing environment or just want to access your home network securely without exposing extra services to the internet and without the mess that comes with setting up and maintaining a VPN server, ssh tunneling is your rescuer. In this post, I’ll tell you how to setup an ssh tunnel to your home network easily. Also look for some bonus tips at the end

This article assumes that you have already installed and setup a ssh server (you can probably use openssh). Also, it assumes that the ssh server is accessible from the internet (i.e. you have appropriately forwarded the port on which ssh server is running). I’d also recommend that if you do not have a static IP for your home network, then sign up for a dynamic DNS service (I use dyndns.org) so that you can access your home network easily by using a domain name (e.g. myserver.dyndns.org) from outside.

Now, here is a step by step guide on what to do on your Android Phone (I’m doing this on a Nexus one but should be same for you as well):1. Install an app called “connectbot” from the android marketplace. It is a FREE ssh client for android.

2. Open it and add the IP (or dynamic domain name as suggested above) and the port on which ssh server is running to the bottom and connect.

2. Once connected, press the menu button and select the icon which says “Port Forwards”

3. On this screen you can configure the ports to be used for tunneling. As you can see I already have my firefly server port configured for music streaming over itunes’ DAAP protocol. Now, you can press “menu” button and click on “Add ports” and go to step 4.

4. You will see the dialog box as shown below. Here you can configure mainly two types of ports.

4a) First is for services that you want to access already running on your home network. e.g. in my case, I have a firefly media server (mt-daapd) running on a port “12345″ and I want to access this just like I was on LAN over my home wi-fi. In such a case, select “type” as “Local”, source port as , say “56000″ and destination as “ip:port” where ip is the your home local area IP of the machine on which the server is running (My server runs on router itself, which has IP 192.168.1.1) and the port is the actual port on which server is running (e.g. 12345 as we mentioned above). After doing this, just open the respective client app on your phone which wants to connect to this server and enter “127.0.0.1″ as the ip and “56000″ as the port to connect to and it will connect to server as if you were on your home network even over 3G or your office wi-fi.

4b) Secondly, you can use this tunnel to route all traffic to internet through home connection. For this, choose the type as “dynamic” and source port as, say, ” 56001″. You don’t need to select a destination port here because any traffic that comes over this tunnel will be routed back to the internet using the destination ip and port as desired, e.g., specified in a browser’s address bar.

Bonus: As I promised above, here is the bonus. For media streaming, you can use mt-daapd or firefly server on your home network, especially on a router like asus wl-500 or any other hackable router with custom firmware. For more info about how to set it up, you can check these posts: Latest Firefly server for your router and firefly sqlite error solution.  For android side things, install the “DAAP Client” app from the market place and click on “Add server” option and follow step 4a as mentioned above. And there it is, your own music streaming service anywhere in the world, over edge/3G or any other network

© Shantanu Goel | SSH Tunneling On Android

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We all know that Android does not allow the camera LED to be controlled directly from apps and hence, you cannot use the camera LED as a Torch or Flashlight unless you are rooted. There are many flashlight apps on the Android Market Place but none of them will work for you if you don’t have a rooted phone. BUT this changed recently. I use a brilliant app called “quick settings” which keeps an icon in the notification bar and I can pull it down and change any settings without leaving other apps. It has a flashlight function but so far it used to work by turning on the screen with a white screen, which was a less than ideal solution. I upgraded to the latest version a few days ago (1.9.4 p1). While messing around with the settings, I wandered across the flashlight settings which allows you to choose what kind of flashlight you want. Now, I’m not sure whether this setting was present earlier or not but I decided to give it a try and chose LED instead of screen (Screenshot below):

Once done, I went back to the main screen and pressed the flashlight icon in the top right (Screen shot below) and voila! my camera LED switched on. I’m a happy camper now as this is a life saver many times. Try this out for yourself by searching for “Quick Settings” in the market and let me know if it works on your phone too (mine is a nexus one).

© Shantanu Goel | Camera LED As Flashlight on Non-Rooted Android Phones

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Recently I came across a weird error while trying to run firefly itunes server (mt-daapd) on my router (Asus wl-500w). It had something to do with sqlite and gave a vague message “Unable to open database file”. After going bonkers for a short time, I solved it and this is how.

One of my hard disks crashed recently and unfortunately it was the one I had connected to my router to serve media to me all over the house (through PS3/laptop) or when I travel (through laptop/phone). I had all the data backed up but somehow didn’t preserve the firefly server. I rebuilt the server from source using my own guide (Thank God I did it. I wouldn’t have been able to preserve my sanity finding all that out the hard way again.). But after doing all the installation and reconfiguration, it gave me a weird error “unable to open database file” every time and exited. I checked the permissions on the songs3.db file (in /opt/var/cache/mt-daapd for me) and made it writable by all but the issue persisted. I changed its ownership to the user under which firefly was running but the issue was still there. Finally I found that the server (or maybe its an sqlite thing) was trying to create a temp file in the cache directory for the transactions and since the user with which it was started, didn’t own the directory it wasn’t able to create the file in it.

So, the fix: I did a “chown <username> /opt/var/cache/mt-daapd” on it and voila! the problem was fixed. I am a happy man now since I own a new android phone since last time and now able to stream all my music to my phone through itunes (daap protocol) server over an ssh tunnel

© Shantanu Goel | Firefly / sqlite error “unable to open database file” Solution

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Update: Made a minor update for a small bug that can make wi-fi keep reconnecting in quick succession.

Pushed out a new update to my Android App Wi-Fi Keep Alive today. This update brings in another work around for the issue where the wi-fi is alive on the phone and it is also connected to the network but is somehow unable to send/receive any packets to the network. The new work around will automatically re-associate your phone with the wi-fi router if it detects such a situation. This seems to make it work properly again for sometime. When it fails again, the workaround kicks in automatically again. This is not an ideal “fix” as such because streaming apps like Pandora radio etc might have a hiccup because of this but it is unavoidable as of now and atleast the notifications for mails and other things etc will work fine because this state stops even the mobile data network from taking over since the phone perceives that wi-fi is connected but is not working actually.

The other things include support for small screen devices like Xperia X10 mini, some optimizations for size and speed, some icon sizes and UI tweaks for compatibility with different screen sizes and android versions. Please try it out from the market as usual and let me know how it goes. You can find the details and QR code for downloading etc here: Wi-Fi Keep Alive

© Shantanu Goel | Android App Wi-Fi Keep Alive updated to 1.4.1

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Recently I found an issue with my asus wl-500w wi-fi router that I wasn’t able to change the channel on which it was transmitting. I moved to a new location which was totally jam-packed with other wi-fi networks using same channel as mine which was hampeing my connection. I tried for umpteen number of times. Changing the channel through the web configuration did not give any error but I found that it was still transmitting at channel 1. I confirmed by checking on the “Status & Log” page, checking the logs, and running “wl status” command through ssh and they all confirmed that it was transmitting at channel 1 only, no matter what I set it to in the configuration. I even opened an issue in the firmware project for the custom firmware (by oleg and lly) that I am using but they weren’t able to help me as the wi-fi drivers are binary only.

But by sheer chance, I stumbled upon the solution finally by trial and error. The solution is that you should set the “Bandwidth” to 20 MHz in wi-fi configuration if you are using 802.11 G. If you set it to 40 MHz then it gets stuck somehow but as soon as I changed it to 20 MHz, I was able to see the channel change immediately after reboot. Here is the screenshot of the page where you can find this setting.

© Shantanu Goel | Cannot Change Channel Problem With Asus WL-500W

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Skype on linux works great but the problem that I faced was that it does not handle the buttons on the bluetooth headsets. My wife uses skype to call into her work related conference calls and was pretty frustrated that she had to keep sitting in front of my laptop (her laptop didn’t allow to install skype) just to switch mute on and off. So, I whipped up this little trick to do so. Here is how:

1. First I looked at the skype API (pretty simple, based on dbus). Also found a sample script somewhere that allowed to answer and hang up calls through skype API.

2. Modified the script to switch the mute on and off instead of answering/hanging up. Script can be downloaded at the end of this article. You can also modify it to take some other action that you want.

3. Install “blueman”. If you are using Ubuntu, just type “sudo apt-get install blueman” in shell.

4. Once blueman is installed and you have done your headset pairing etc, right click on the blueman icon in the system tray and click on “Local Services”.

5. In local services, click on headset tab and you can see a input box where you can give the path of a program/script which will be run whenever the “answer button” on the headset is pressed. This is important to note that blueman only supports the answer button and nothing else and I didn’t have the inclination to develop a full-fledged AVRCP compliant program to capture other buttons as all I was interested in mute functionality. You can see the screenshot of this below:

6. Make sure that you give the path where you saved the script that you downloaded in step 4 and you are all set now. Make a call and click on the answer button of your headset to see the magic happen

Let me know if you have your own hacks like this or know of a way to have a full fledged capturing of all headset buttons.

© Shantanu Goel | Mute (or Answer) Skype Calls with BT Headset Button in Linux

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If you are creating a custom Dialog for Android, and following the Android Developers’ Creating Dialogs tutorial, then most likely you would have faced a Force Close with this exception showing up in logcat. I did too. Although I figured it out quickly, it might not be easy to find out for many, so posting it here for reference. Basically, the code given in the tutorial goes something like this:

Context mContext = getApplicationContext();
Dialog dialog = new Dialog(mContext);

dialog.setContentView(R.layout.custom_dialog);
dialog.setTitle("Custom Dialog");

TextView text = (TextView) dialog.findViewById(R.id.text);
text.setText("Hello, this is a custom dialog!");
ImageView image = (ImageView) dialog.findViewById(R.id.image);
image.setImageResource(R.drawable.android);

All looks well, but when you execute it, you will get a Force Close. The error appearing in logcat would be something like this:

Uncaught handler: thread main exiting due to uncaught exception
android.view.WindowManager$BadTokenException: Unable to add window — token null is not for an application

It isn’t apparent immediately that what is causing this error. The very first line in the code “Context mContext = getApplicationContext();” is the culprit.

Solution: Just replace “getApplicationContext()” with “this” (i.e. “Context mContext = this;” ) and it will work fine.

Explanation: As to why this is exactly an issue, I’m a bit fuzzy about it myself but this much I’m sure that the contexts that you get with getApplicationContext and this are different. On reading about this function from Android SDK help:

Return the context of the single, global Application object of the current process. This generally should only be used if you need a Context whose lifecycle is separate from the current context, that is tied to the lifetime of the process rather than the current component.

I think this would mean is that getApplicationContext returns a context which is for the application itself and not the activity, while “this” would give you the context of the activity in which you are creating the dialog. I think since it is the activity which is associated with the UI (and for whom the window has been created), using the application context would have caused the crash here.

© Shantanu Goel | BadTokenException Error In Android Dialog

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