I've liked using LogTen Pro on my home computer & macbook, plus iPhone (I switched after losing some data on a free Windows logbook a couple of years ago--you get what you pay for). Yes, you have to buy each version you use on separate platforms--but I was able to install the computer version on my older Mac, and now my macbook laptop. You do NOT have to upgrade to keep using their products, but you will lose iCloud backup on the next version. If you purchase their product now, it's a free upgrade when they release. There are more comments in the other thread on APC, and on their website, describing how they cannot issue a "bundled" version, as Apple restricts that. I will wait and see on the upgrade, since I'll have two/three options for a discounted upgrade over three months.