I want to integrate devise-token-auth with react-native. ``` fetch('http://localhost:3000/auth', { method: 'post', body: JSON.stringify({ config_name: 'default', first_name: this.state.first_name, last_name: this.state.last_name, email: this.state.email, password: this.state.password, password_confirmation: this.state.password_confirmation, }) }) ``` Unable to post the json in correct format, am I doing something wrong ? ### There is very less documentation on fetch api