There are 4 places in the app from which you can book public transport, all accessible via the Home view button.
First, at the top of the screen, there is the Search bar
Clicking on this opens up the journey planner (Fig.1), where the from field is pre-filled as your current location and you just need to enter the address of the destination or choose from your favourites, which are displayed under the destination field.
The From field can be edited once you have pressed enter in the destination field. This gives you a list of public transport options to choose from and a taxi option (Fig.2).
Choose the best option for you and you will be issued your public transport ticket before your journey begins.
Second, you may book public transport via Favourites (If you haven't added favorites please do so - read more here) which are below the Search button (Fig.3). By simply clicking on a Favourited address you get the same results as explained above.
Third, you may book public transport via Calendar entries from "Upcoming"(if you have allowed Calendar synchronization when you first installed Whim app) (Fig.4). Here you may book public transport straight from your calendar entries, as outlined above.
Finally, you may book public transport via the Whim button (Fig.5) - the fastest way of booking public transport.
Press the 'W' in the middle of the navigation bar and this opens the Whim view. From there choose Public transport(Fig.6) and then the ticket corresponding to your journey (Fig.7).