Stretch 15 is a straight-forward web app designed to get you stretching more. You just indicate whether you’re in the office or at home, and it gives you a timer and indicates which stretches to do, when. The site tracks your total stretch time and your daily stretch ‘streak’, if you’re into that type of tracking.
A good complement is Workout.lol, which is a similarly no-nonsense web app where you select your equipment (bodyweight, bench, band, etc.) and which muscles you want to work. You’re then presented with a routine and videos, based on data from MuscleWiki.