There are many frameworks out there which mimic the user interface of iOS but not much exists for Android

Fries is a solid HTML-CSS-JS framework for creating Android-like UIs both for real-world usage and prototyping.

The framework has all the major components like forms, action bars, lists, buttons, spinners or tabs.

It is also optimized for PhoneGap and can be easily converted to a native app.

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Least.js is a jQuery-powered image gallery that can display images in a Pinterest-like layout.

The images are displayed from an unordered list where their order is randomized on each load.

Any clicked image doesn’t load the bigger version in a modal but by sliding other items down and the big version on the top (kinda similar to Google Image search).

The gallery makes use of HTML5-CSS3 features and works good on responsive layouts.Advertisements:
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Sliding side menus are widely used in mobile apps as they are only visible on-demand and save space.

jQuery.mmenu is a slick plugin that brings the same behavior into any -mobile- web layout.

It transforms unordered lists with unlimited sub-lists into menu items and has multiple options for customization.

The options include the position of the menu (left/right), if a counter for the menu items will be displayed or not and more.

jQuery.mmenu can also be controlled (opening, closing and toggling the menu) with simple functions.Advertisements:
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When building and updating native mobile apps, testing them can be a pain as this may require including an SDK or recompiling the app.

Appium is an open source framework which helps automating mobile app testing from any language and any test framework, with full access to back-end APIs and DBs from test code.

It works for both iOS + Android apps and tests can be written with Java, Objective-C, JavaScript, PHP, Python, Ruby, C#, Clojure, or Perl.

The framework is Mac OS X only and requires Nodejs to run.Advertisements:
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HTML5 Up! is a website that creates and shares very good-looking and free HTML5-CSS3 templates.

All the templates have responsive layouts (down to mobile) (uses Skel.js) and they are compatible with all major browsers.

There are already 10+ templates where new ones are added within time and they can be used freely under the CCA license for both personal or commercial projects.

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When building websites with scripting languages that require compiling (Sass, Less, Stylus..), compiling them manually (or via refreshing the page) is usually an extra step.

Prepros is an open source application for Windows OS that can do that automatically for Less, Sass, Scss, Stylus, Jade, Coffeescript, Haml and Markdown.

It auto-compiles the source and injects the CSS (also HTML and JS) to the browser so that no refresh is needed.

There are options for the compiling process like the output format or its style (compressed, nested..).

Prepros also has a built-in + static HTTP server for testing any ajax requests.Advertisements:
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We use labels on many parts of web design like providing information about images, form elements, videos..

Label.css is a simple-yet-useful set of CSS rules that provide a global label usage.

Each label can be attached to any element, positioned how we want (right, left, top, bottom, inside, outside) and can be animated with float or fade effects.

It works by adding pre-defined classes to the elements and the content of the labels are stored inside the data-label attributes of each element.

Simply, a good addition to any stylesheet (or CSS framework).Advertisements:
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Skel.js is a tiny JavaScript framework (~6kb gzipped and minified) that simplifies building responsive layouts very much.

It has a JavaScript-powered and 12-column grid system that can handle any type of complex layouts + has easy-to-understand rules.

Managing breakpoints is just about adding the width ranges in the options of the skel.js‘ main function.

There is a plugin system for extending it further (a UI plugin is mentioned to be released soon).

Also, many helpful options exist like the ability to applying reset.css or normalize.css and defining the box model instantly.Advertisements:
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When working with JSON strings, it is usually hard too understand their hierarchy at the first look.

JSONmate is a web app that can beautify (and uglify) JSON strings where these strings can be directly pasted or loaded from a  remote URL.

Also, it has a very nice visual editor for customizing the data and a visualizer that provides a different view for it.

JSONmate has support for JSONP too and it is an open source project.Advertisements:
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Users with modern browsers are increasing each day and making use of features like HTML5 audio sounds more and more logical.

AudioPlayer.js is a jQuery plugin for quickly placing a HTML5-powered audio player to any web page.

The player’s interface is chic (doesn’t use any images for that), has a responsive layout and touch support.

It has the major controls (play/pause, volume and duration) and weights only 4kb.Advertisements:
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