A timer is a timer. The app ones work great for a lot of stuff. My Pocket Pro is at the foot of my bed, so it's just what I always use.
I've been doing a lot of dry fire, back to the fundamentals stuff. Which is a bit difficult without proper instruction, but whatever. Trial and error.
My timer was getting a bit of neglect. These past couple weeks, and especially these past couple days... it's been earning its keep. That said, it shows I haven't been using it. My open draw is consistently at 1.5, and my concealed draw is consistently 2.25. I'm also not any faster AIWB than I am OWB strong side... which is really, really, REALLY lame.
My reloads are also DISGUSTING. I was hitting about 1.75 for on target, reload, back on target (no slide release). Very disappointing. I really need to get into a class to hammer fundamentals.
Also, go shoot IDPA and USPSA. It's fun. Ignore the a-holes. There's always some. For me, it's usually less the gamers and more the fudds who pretend they know how to shoot (among a billion other things).