Have the input box selected by default as soon as you log in.
This might seem kind of odd, but when I use a bluetooth keyboard I don't want to have to tap on the input box every time I open the app after it has been closed (I.E. from the multitasking bar, or similar.(I don't know about when I turn off and back on my device, but It might happen then also.).). Please excuse the odd punctuation, it was just a guess.