A study of world's most popular travel apps shows that 100% of iOS apps failed to receive a passing privacy or security grade. Researchers from the firm Zimperium tested thirty "best deal" travel applications, covering flights, hotels and car rental to better understand how they manage users' privacy and security risk. According to Forbes, some 97% (29 apps) of the iOS travel apps tested were found to be able to take screenshots of the full user interface, which could enable an attacker to "understand everything from installed apps to user credentials". As for the security, 100% of the iOS apps also failed, while Android apps had a 97% failure rate.