A panel of researchers who focus on looking for attacks and bugs at various levels of the mobile device and infrastructure said at Black Hat that there are so many ways an attacker can compromise phones from the infrastructure all the way down to the application level. Going after the device firmware is one potential method, as is attacking the mobile infrastructure itself. Some of the panelists said that restricting what apps users can download and taking away their ability to set permissions for those apps would be a good step in the right direction.
Source: https://threatpost.com/securing-mobile-devices-may-be-impossible-task-080411/75512/