If one of these saved you a subscription, you can put a few dollars toward the next one. It unlocks nothing, and the apps stay free whether you do or not. Pick whichever you already use.
Tips go through Buy Me a Coffee, PayPal, or Cash App. I see an amount and a date, and nothing that identifies you unless you add a note.
Apple's developer account, the Mac this gets built on, the AI that writes the code, and the sites and data sources the apps lean on. Nothing here pays a salary. If it ever covers the costs, that's the goal.
Every app also has a small tip jar in its settings. Three amounts, through Apple, and it unlocks nothing. Same deal as here, just closer to hand.
Rate an app on the App Store. Tell one person who'd use it. Reply to a build post on X. Each of those is worth more to a free app than a dollar is.