I worked at a startup, Javaground [1], where we ported and developed games for J2ME phones. We had a room full of dressers full of all the different mobile phones of the day. Each phone had different implementation quirks, such as variable audio delay when playing a file, audio/image formats that were faster/slower, odd button events (some used press, some used ondown, some had no ondown, etc). A lot of our work was…
Ah, it's nostalgia-a-clock. I worked on Skype for J2ME with a 3-4 person dev team. Custom UI kit, 128x128 screens, 128kb available memory and other fun limitations.. I think we re-wrote our text rendering/styling/wrapping code more times than there were actual releases of the app :) I honestly miss these times - it sparked so much creativity when one needed to achieve something in such a limited environment.
As someone from the c64/apple][/atari generation... it was constantly amazing to see how much people could push a single device. Lots of creativity, as you say. But... we seemed to hit a wall with the whole j2me-era of "just get creative to work around things!" mindset. Because, IIRC, there were dozens of different devices that all didn't work the same way - you'd have to get really creative to get things to work in 128k, but then do it again and again and again for each target device.
There were millions of C64 units in people's hand in, say, 1986. And similar for Apple ][ units. You could be assured of a decent audience/sales/users if you ported to that platform, even if there was a lot of 'creativity' to deal with. The j2me device world always seemed a lot more fragmented to me (but maybe it wasn't?). But just saying "this runs on a java device" was different from distribution - allowing 'regular' people to get something in to a centralized store/distribution point seemed another big win for the iPhone world.
EDIT: fwiw, this made me spend a few minutes in youtube looking at old c64 and apple and Atari demos. what people ended up doing with those devices - years after they were mainstream - is still crazy to me.