I'll second that, no app needed. A small notebook with a "table" per planned exercise and a ball pen are always in my sports bag, so its ready to go when its training time.

The phone appears to be a distraction for many people I watch at the gym, over-extending the rest between sets while watching social media. The minimalism provided by the paper notebook is what I prefer instead.

Honestly for beginners just building a habit of regular lifting is by far the most important thing. Progressive overload, going to failure, periodization etc won’t do much if you don’t have consistency. My advice to beginners would be to go to the gym 3 times a week and do whatever interests you for about 45 minutes. Once you have that habit nailed down for 6 months then we can talk about more advanced stuff.