I just realized recently that, in many cases, you really need to use a virtual number to receive verification codes, such as registering for overseas websites, testing APIs, or creating a secondary account. Buying SIM cards before was too troublesome, but I later found that SMS verification platforms are truly a lifesaver—they provide temporary phone numbers, and the verification code is displayed directly in the backend, protecting privacy and saving effort.

However, I encountered many pitfalls early on. Some platforms simply don't receive messages at all, some have delays of half a day, and only after experimenting did I figure out which ones are reliable. In summary, SMS-Activate and 5SIM perform the most stably, with verification codes arriving within about 10 seconds and covering many countries. For domestic applications, Xiaoniao SMS and Super Cloud SMS are good options; US numbers generally get a response within 10-30 seconds, and Chinese numbers are even faster. There's also Getsmscode, which is cheap, but it tends to have delays on less popular platforms.

There are a few points to note when using SMS verification platforms. First, shared numbers are often already registered, so it's recommended to prepare several backup numbers. Second, verification codes can indeed be delayed, especially for less common countries or apps; in such cases, switching numbers or refreshing usually solves the problem. Also, don’t buy cheap, unreliable services—choose reputable platforms. Lastly, never use these as your long-term primary number, as privacy and security are not guaranteed.

My experience is that if you're just testing APIs, any platform that supports API access is enough. But if you want stable registration on a specific overseas website, it's best to load multiple numbers and be able to switch quickly if one becomes invalid. Many platforms also support one-click number switching, which is especially practical and helps avoid wasting time.