Well, many of the magazine apps themselves are 'free' but subscriptions to most of the publications will need to be bought - currently, I'm using the Zinio App - have paid subscriptions to PCMag, iPhone, & MotherJones - I also receive Sound&Vision & PCWorld as mail subscriptions but may switch over. The Zinio app works well for me w/ these present subscriptions.
Yeah, apps Zinio are good. Or just do a search for 'magazines' in the app store. I purchase several when I choose. Don't bother with subscriptions, just buy individual copies.