A phone (with good battery) will last 4 to 5 hours with a full battery.
A good rule of thumb is that you use about 20% to 25% of your battery per hour when navigating with your smartphone. This is a guideline, the actual consumption also depends on the quality and age of your battery.
Be aware!
If your battery power is running to its end, it will deteriorate faster than at the beginning. So if you start at a full 100%, you will be at 80% after about an hour. However, if you only have 20% battery at the start, you will probably be at the end of your battery after 45 min.