Monitoring your expenses is the first step to reducing them, and while there are many general purpose apps for that, is designed specifically to monitor the costs of running your vehicle.
You can track fuel costs, mileage, gas consumption, maintenance costs and more, and build charts of your fuel efficiency.
Monitoring this information could be useful for anyone, especially if you want a clearer breakdown of how much it actually costs to run your vehicle, and by seeing spikes in your spend, for example at certain gas stations, you could potentially cut your costs by filling up elsewhere.
But Drivvo is especially useful for anyone who has a work vehicle or fuel allowance and needs to monitor their running costs for that.
The core app is free, but for $6/£6 per year you can back your data up in the cloud, synchronize it between devices, export it into a spreadsheet and get rid of adverts.