I'll echo JBone's recommendation of Pebble. Mine is first generation (the Kickstarter edition), but the software is updated for all versions equally. The watch operates via blue tooth with your phone, both Anroid and Apple.
I use Misfit (tracks steps), Runkeeper (walking & biking) and FreeCaddie (golf) apps on my phone, and the data shows up on my watch. There is a swimming app which I haven't tried. Plus, phone, text, email and other notifications show up on my watch.
You can buy the original version for under $100, and I've seen ads for refurbished watches for $60. Very affordable and functional.