laravel - auth in laravel API

I have a question about token expire in laravel 5.1 . when a user login to app in mobile, app send a token with expire time to mob. mob use this for 1 hour. now after 1 hour how app get new token? we have to send user to login page and user have to login per 1 hour? I can't know how can i refresh token before expire that.

via Chebli Mohamed