For Managing Color
Great toolby which you can upload, create, and edit color schemes of your choice.
It is an extension with chrome with color related tasks; it includes a Color Picker, Eye Dropper, Gradient Generator and many additional advanced color tools.
For Managing Typography
Google Web fonts
Google’s numerous web fonts for great use. They are free and incredibly easy to implement into our projects.
This is best resource for free, hand-picked, high-quality, commercial-use fonts.
For Managing Wireframing
moqups is a HTML5 app used to create wireframes, mockups or UI concepts.
It is an entirely free service which you can store on your online google drive with your gmail.
For Managing Layout and Boilerplates
bootstrap for pre-made user experience. There are numerous features bundled with the framework, easy to implement.
Less is a framework dedicated to making websites truly adaptive with 4 layouts and 3 sets of typography presets, all based on a single grid.
It is a light weight structure benefits those who are looking to get started without studying up on how the framework really works.
For Managing Content
Most popular blog posting platform with content management.
Joomla is another popular Content Management System used by millions of users worldwide.
Drupal is an open source content management platform, It’s built, used, and supported by an active and diverse community of people around the world
For Managing Useful Apps, Actions, and Resources
GuideGuide is an awesome photoshop extension which allows you to create perfect grids on the fly; you can create more accurate columns, rows, midpoints, and baselines with one click by using GuideGuide
iOS Photoshop Actions & Workflows
If you’re designing an app icon for an iPhone app there is a great action which resizes the app to each pixel width and height necessary. Like this many useful features it contains for developers.
By People is a great and simple website feature packed with resources which are free and easy to use.
Temboo normalizes access to APIs, databases, and more to save you time and provides required creative space.
With Respond.js, you can use media queries efficiently.
It works on the premise that you are already using the highest-resolution images on your site, and also offers a ton of customization options. You can set breakpoints to match your CSS, set the quality of the generated JPGs, set how long browsers should cache the image for and much more.
As the web market and mobile market going up, demand for responsive web designing is increasing so, these tools will definitely help while designing and adding your creativity in your web pages.