As the mobile web transforms the development process, a few free mini tools have surfaced in our arsenal to aid building advanced web properties in an ever-changing world.

TinyPNG

This web-based PNG compression service really shrinks those bloated PNGs while retaining the alpha layer too.

http://tinypng.org/

Responsivator

This handy service displays a number of configurable screen sizes for responsive testing.

http://dfcb.github.com/Responsivator/

Adobe Edge Inspect

Part of a suite of tools for contemporary web development, Adobe again leads the way in comprehensive toolsets.

http://html.adobe.com/edge/inspect/

Moqups

A very advanced and simple-to-use web tool for creating a wide array of wireframe mockups.

https://moqups.com/

Snipplr

Get your many, many snippets of code for all manner web dev needs, including HTML, CSS, PHP, jQuery, and more.

http://snipplr.com/

fontBomb

For when you’re going insane from all the multi-device madness, plant a few fontBombs to get some much needed relief!

http://fontbomb.ilex.ca