Untapped.gg is an excellent, all-in-one tool that I love using, even more so with Personal Stats. It's given me so much insight into my game and favourite decks, and I know that casual and competitive players alike will love it too!
The Untapped.gg deck tracker and personal stats go hand in hand, similar to a Healer's Hawk and a Mentor creature. Much like the little Hawk you'll be able to see your skills grow over time as you gain more knowledge. Great for both Limited and Constructed.