The benefit of what Apple did is that when the market needs 64 bit it will have been deployed for years. Transition issues are already sorted out. But iOS apps

The benefit of what Apple did is that when the market needs 64 bit it will have been deployed for years. Transition issues are already sorted out. But iOS apps are also more likely to have issues on a 64-bit CPU, since they are written in (Objective-)C. Since nearly all Android apps are written in Java, the transition will likely be far less eventful.