Last used App as one unique user context information in mobile phone data, it also takes a very important role to decide the next mobile App to use.
When people launch mobileApps, they usually follow a sort of latent pattern.
For example, auser reading papers on the mobile device may meet difficulties forunderstanding some words.
In such case she will start a dictionary App.
Similarly, a user shopping online will probably start a payment App after hunting a desired commodity