I will be writing my app mostly from my laptop but I am planning on the possibility of bringing on other people, particularly a designer. Source control is a must even if you are designing your app solo. As far as I am concerned there are two options Git or Svn.
There are tons of comparisons of these two forms of source control so I wont waste my keystrokes. Since I will be developing this app at home, in coffee shops, and for the most part on the go there is one feature that Git has that I feel I cant live without: local checkins. For that I am willing to pay $7 for a github micro account. I will be keeping my account private but watch my github account for sample projects and utilities. I am convinced that keeping things as open as possible is the way to go.