Why I think iGP Manager crashes is...
Memory used. The resources on loading is doubled from 3.x. In 3D, up to 100+ of resources are used while loading, while 2D uses up to 60+.
The device can't handle it. 1.4GB+ is stored in iGP resources, meaning low-end devices CANNOT possibly handle it.
WebView problems. WebView may also be a problem because it can't handle the game on low-end or even high-end devices.
Performance Issues. The performance is slow on low-end, slow that the device can't keep up and crashes.
Lack of CPU power. If a low-end device is used, it might not be fast enough to keep up.
Sound quality. The quality may be too much for low-end devices.
You could fix these!