@ Dan -
From what I know, Jim is running Windows on the desktop, but has a newer iPad, which is his only current option without buying a Mac of some flavor...
GarageBand does not work on Windows, but does work on iOS and Mac.
Logic used to have a Windows version back when it was a product by a company called eMagic, which Apple bought back in 2003, and then shuttered the company, and internalized Logic as an Apple product and then made it Mac-only.
The closest thing to GarageBand on Windows is a program called Sequel by Steinberg, also the makers of Cubase/Cubasis. last time I checked it was ~$99 USD for the basic version, but project files are not compatible with Garageband nor Logic (nor ProTools either).
There are a few other DAW programs that have versions for all three of Mac/Linux/Windows, such as:
Tracktion
Ardour
Harrison MIXBUS/MISXBUS-32C
BitWig Studio
and Ableton Live has both a Mac and PC version.
Hope this helps.
@ Jim -
Apologies for speaking of you above in the third-person
source: longtime computer geek going back to Z-80 and M6502, and M6809 cpu-based system in 1976, then PC since 1981, switched to Mac in 2005, and now use Mac and iOS only for music, but Linux for main desktop since December 2014.
Also having worked professionally both in IT and as an audio engineer for 35+ years, I've seen lots and lots of hardware and software systems that I've used both at home and in pro studios.