Is simplenote for iPhone worth buying?

I’ve yet to find an app that is worth buying.

or is it the kind of thing apple will eventually implement for their native notes app, and render simplenote useless?

Based on their own FAQ I certainly wouldn’t buy it. For one, they allude to the possibility of your senstive information being stolen (credit card #s, social security #, etc). For two, the number of “updates” and “seriously considerings” and “future improvement“s makes me assume that they’re going to (eventually) come out with a better version that you’d have to pay for again.

Evernote fulfills pretty much the same function and it’s free.

It also syncs with the cloud as well as desktop applications for both Mac and Windows computers.

This is a category where there are tons of apps for both note taking and task management, most of which are free. You could give some of those a try and if you can’t find a combo that meets your needs, then purchase.

How are you going to a job at an Apple Store unless you can answer such a question yourself?

Play with the app. Do some homework.

I’d suggest reading the reviews on the app (on the Apple Store) (some are very positive, but there are many negative ones, too). If you want a note replacement, simplenote or notespark or awesome note will all work. But if you’re wanting a really great to do manager, then Things or Omnifocus is what you want. Both have a Mac desktop client and both have their pros and cons. I wound up going with Omnifocus because I’m a more linear thinker, but Things is also really well implemented and works primarily on the concept of tagging. Omnifocus is constantly updated and they are adding tagging as well.