Here’s one tip of which I was unaware:
You may vaguely recall hearing something about rechargeable batteries and the “memory effect.” You know, that if you don’t “teach” your rechargeable batteries their full potential by taking them from totally full to totally empty, they’ll “forget” part of their capacity. Well forget all that. Right now. It does not apply to your phone.
Battery memory is a real thing, but it applies to nickel-based batteries; your trusty sidekick (literal Sidekick or otherwise) doubtlessly has a lithium-ion battery, and it needs to be treated a little differently. Specifically, it should be topped off whenever you get the chance.
Read the whole thing–it will help you get more from your phone until upgrade time comes around.