You pay $5 for Tweetbot, and they work delivering updates for years before asking for another (usually b/c of many new features or hard work updating the UI for

You pay $5 for Tweetbot, and they work delivering updates for years before asking for another (usually b/c of many new features or hard work updating the UI for modern iOS) It's one of the most polished apps around. You don't owe the Developer's time indefinitely from one $5 purchase, and you're free to move to an alternative. I'm happy to continue to support the apps I love -- they generally aren't asking a whole lot. Additionally, in the case of Twitter clients, they also can't add a lot of new customers b/c Twitter has capped their allowed clients. If they didn't charge customers again, they wouldn't be able to sustain the work with new ones.