This often happens if you download a version of Summertime Saga that requires more RAM than your older iPhone has. Try an older, more stable version of the game (check the official website's archive section) or close all background apps before launching.
You can also download Summertime Saga from third-party app stores, such as:
Platforms like iOSGod or Panda Helper sometimes host versions of the game.
While there is no "App Store" link, users often rely on sideloading or third-party installers. , as these methods are not officially supported and can sometimes lead to security risks. Using IPA Files & Sideloading Tools: