The top row shows GLAR, then Me with your name and sign out. The site master also sees Site manager with Home, People and Organizations.
The second row starts with the band box. If you run more than one band, pick the band here. Next to it is your role: Band leader, Band manager or Support access. Then the tabs, in groups:
A number on a tab means something needs you. On Gigs it counts gigs with no offers sent or with an open chair. On Polls it counts polls still collecting answers.
Below that, the Next: bar links to your next job. Gig and poll pages also show a numbered step bar so you can see where you are. Tap any small ? next to a field for a short tip.