For the original poster, that may not be the issue. Depending on the type of tablet he's using it could be a Flash issue. When the iPhone came out, Apple dropped all support for Flash because of similar issues. Among other things, Flash requires more memory and processing power than most other types of code/programs.
However, some other phones and tablets along with their accompanying operating systems have supported Flash on their devices. While very little of the web still uses Flash, Google still allows Flash ads. A tablet that really doesn't have the power to run a Flash ad or is otherwise using all of it's available resources may crash when Flash attempts to load.
The tablet owner could try making sure other applications are not running on the tablet, but you never know when and where a flash ad is going to show up so that's a bit unrealistic.
If I remember right, there is an option to disable Flash based ads within Google AdSense. Adsense would then go to the next most appropriate ad that is not Flash based. I believe that would be the simplest option, but if it cut significantly into the revenue, the site itself could be altered to hide the offending ads from mobile devices.
Sorry I didn't see this earlier and hope it helps.