Something I was just made aware of on another forum: an iPhone/iPad App for modelling:
https://itunes.apple.com/us/app/imodelkit-full/id465661238?mt=8The colour charts contains samples of just about every brand of paint known, clicking on a paint will give you info about it (what size pots etc) but will also give you matches to other brands with colour samples. The app gives you a mixing pot will allow you to mix paint brands and get a colour sample. You can also take a photo of an object and convert that into a colour sample that will even give you an brand equivalent! Paint mixes can be saved for later.
It also has a scale conversion calculator. Also included is a tool that will give info about different brands of plastic for those who like to scratch build.
A note pad is also included ...for shopping lists. Great for those trips to the hobby shop.
You can get it for free with ads (unnoticeable after a while and no popups) or pay for an ad free version. Both work the same.