title: Trusted Execution Environment (TEE) on iOS and Android
body: <p>In the FinTech area there is a lot of talk about the use of Trusted Execution Environment (TEE). I know that on both iOS and Android it is possible to use some key store API's to generate keys and use them for signing/decrypting. But the code oneself writes is running as a normal app.</p>
  
  <p>My question is, is this the only available use of TEE? Or is it possible for a normal application developer (i.e. one who isn't the manufacturer of the handset etc.) to write an app where the code in the app itself runs in the TEE? I have not been able to find documentation with Google or with Apple that describes how this would be done. Is there special API's available?</p>