Such apps can launch battery and bandwidth-intensive operations hidden in the background of the device that linger even after the app is exited.
The apps request access to settings like preventing the device from sleeping, modifying and deleting memory and tracking user location, which are often unnecessary for the app's purported function, according to the study released by ad fraud detection firm Forensiq.
Just over 13 per cent of ads served up across apps on Android, Apple and Windows mobile devices were concealed from sight, the firm concluded from an analysis of more than 16 billion views on 12 million devices.
"We wanted to show the public how blatant and obvious and hurtful all this fraud is - not just to advertisers who pay for ads that no one sees but also people using these apps on these tiny devices that are bandwidth-limited and power-limited," Forensiq's chief scientist, Mike Andrews, told 'Mashable'.
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The study researchers built algorithms that hunted for instances when fraudulent ads showed their hand with suspiciously non-human behaviour.
Researchers said users can take relatively simple steps to protect them from running up their phone bills and draining their batteries.
One is scanning app review sections for accounts of excessive data or power usage that may indicate fraud is at play. Another is switching off access to cell data for apps that don't absolutely need it.