there is no way that the phone being used will play up pump device at all,
phone still bounces signals if your using it or not, if a phone could mess up pumps the pumps our phones would be illegal all electronic devices have to pass testing to make sure other electrical devices do not interfere with them.
the blowing stuff up is a american myth that was proved to be fat lazy yanks putting the pumps on auto getting back in the car then getting back out, and a static discharge sparking when they returned to pump handle to remove it, then i think it was very unlikely to ignite it.