in practice, 'real' mobile mining will affect the device used, since the application uses resources such as ram and cpu that work continuously. this intensive use of resources will affect the performance of the device, especially when users install more than one mobile mining application on their device, these applications will work simultaneously and this will slow down the cpu - and on older devices the cpu performance may work harder, causing heat, it can shorten the life of the device. and therefore most miners use old devices, in addition to saving costs, if the device is damaged they only need to replace it with a new one.