My android phones aren't activated. Only work with wifi.
(1) Uber or Lyft works just fine on a non-activated device using wifi I've done exactly that a whole bunch of times.
(2) As I said previously Uber for sure will work fine in a web-browser on most devices even if not officially supported.
(3) As others have correctly pointed out you DO NOT need to book Uber/Lyft in advance more then a few minutes most of the time in any major market pretty much 24/7.
(4) If on the other hand you would be more comfortable having your ride locked in, you would be much better served going with a Limo company although it may cost more. If you would like to look into this PM me I'll see if my company has a local affiliate.