Just got a positive recommendations from designers to look on new version control for designers - LayerVault. Backed with unlimited storage, team collaboration and real-time feedback with updates you can easily manage design changes with customer or a team. It works with Adobe files, adapts to iOS resolutions and seems to be a dream box for any pixel-perfect maniac You can try it for 30 days for free and of course it works only on Macs :) Sleek icon made by the best Russian interface designers from SoftFacade