The thing is, most of these apps that promise prizes end up not paying out or just disappearing out of nowhere, which is frustrating. What works best in Portugal is testing apps with a good reputation on Trustpilot before you start, and going for the ones with small, frequent rewards instead of those that promise the earth. Some still have the option to convert points into mobile credit or shopping vouchers (like Fnac), which is more reliable than waiting for a bank transfer. My suggestion is to actually read recent comments from other people because things change so fast that something could work well today and stop paying in a few months.