I am on linux and have been looking for a character sheet. I have tried a bunch. The only one's I found fill able were autofill which I don't mind so much but I can't fill out a lot of stuff on my computer. Anything that's marked with a zero were it does the auto-math I can't fill out.
Another thing I use mostly open source stuff and won't use adobe products. Nothing against people that do. The people that made the sheets I tried put a lot of hard work into them and I really appreciate it, but they don't work for me.
The only other sheet I found was the a google docs sheet and it does absolutely everything for you. It levels up your character fills everything in and that kind of takes a lot of the fun out for me. I don't mind autofill sheets but when I level up I like to go through the SRD and go back and fill in all the stuff myself. I catch rules I miss and it's just part of the fun for me. I also like to create a lot of my own content so something that does absolutely everything doesn't exactly fit into the game I am playing.
Don't have enough money for any books I am kind of poor but from what I have seen it starfinder looks great. I have enough with the SRD to get the rules and Will be making my own maps/quests/enemies. I know starfinder is young but it really looks like a great game. If I could just find a character sheet that I could fill in but wasn't autofill or something online that didn't do 100% of everything.
I will say this though the sheets I have tried looked great and the people that created them did a really good job.