As a "non-high-tech-phone" user , I use a free java application called Azi`s Metronome. It`s... well, what the name says. It`s a very steady app, does not require much memory space, can go from 30 all the way to 299 BPM.
Also, you can input a tempo you don`t know by tapping it, and you can choose odd time signatures, too. I have it on my Sony Ericsson Cedar and I think it`s a very useful application. The best part is.. it`s FREE!.