As for the pen use and tips wear out I've never replaced the tip in any of the pens I own, but truth be told, I hardly ever use them.
Thanks for recommending the apps. Did you mean
https://www.nebo.app/ ? Looks nice. I don't mind one-off purchase. Too bad they don't seem to be selling the android app outside Google store. I won't ever buy anything from G after they f* me up. Sure the apps in their store are cheap, I had quite a few. However when I moved they didn't let me change the location without revealing a credit card to them. No no no no! The nail to the coffin was when I decided to buy a Play Store gift card to my nephew. I bought it, sent to my nephew but then Google said it's invalid for use outside of USA. I complained to G, then filed a charge back to CC, no luck as the G TOC state things in the fine print on page X.Y... a big f*, so that was it, I deleted G account, losing all of my purchased play store apps without any regret.
Never mind the above story, I'm actually not much interested in hand writting. However I'd like to get better apps for PDF and ebooks handling. I really like the
Book Reader app, but it doesn't have 2 pages view which would be useful in landscape orientation.