The sooner you get in, the better for you as the bonuses for early birds are great.
The early birds bonuses are form of compensation and appreciation to them for the trust they have in the project. Some investors love seeing people investing in a project first before developing confidence sort of
Users will get rewarded for backing the project from the start when they isn't any 'product' as such; however - bitfence look one step ahead of the game and already implemented an iOS app