How many apps do you have on your smartphone or tablet right now? Well, take that number, and multiply it by 0.9. That’s about how many of your apps are a potential security concern according to a new study from Appthority.

The Appthority Reputation Report for Winter 2014 was compiled using data from the cloud-based Appthority App Risk Management Service. Appthority performed static, dynamic, and behavioral app analysis of 400 paid and free apps spanning iOS and Android to assess the relative security and risky behavior of the most popular apps.

Appthority found that 95 percent of the top 200 free apps on iOS and Android exhibit at least one risky behavior. That number drops to 80 percent for paid apps—an improvement, but four out of five paid apps exhibiting risky behavior is hardly something to cheer about. Appthority also discovered that iOS apps are riskier overall than Android apps—91 percent contain risky behavior as opposed to 83 percent on Android.

They risky behaviors vary, but include things like location tracking—found in 70 percent of the free iOS and Android apps—weak authentication, sharing data with ad networks, accessing the contact list, or identifying the user or UDID.

Appthority found that 95 percent of the top 200 free apps on iOS and Android exhibit at least one risky behavior.

There are a couple significant caveats to the idea of iOS being a greater risk. First, Android apps have a much higher presence of accessing the UDID or identifying the user. Apple took steps to prevent developers from accessing UDID information on iOS mobile devices—but some developers have found ways to circumvent those rules.

The other thing that separates Android from iOS is that, although there are more iOS apps that exhibit risky behavior, the Android apps tend to collect more information about the user and the user’s mobile activities than their iOS counterparts.

To sum up, a higher percentage of iOS apps include risky behaviors than Android apps, and paid apps are generally less risky than free apps.

The differences in many cases are small and semantic, though. The fact that iOS has a higher percentage than Android may offer some small consolation to Android users, but the fact that nearly all of the apps on both major mobile platforms exhibit at least one risky behavior should be a red flag for both app developers and mobile device users—as well as for Apple and Google themselves.

The real lesson to be found in this report is that app developers recognize the financial value of gathering user data, and that mobile apps in general have a long way to go in terms of security and respecting a user’s privacy.