You can choose to show your power measurements either in watt, percent of your FTP, or as watt/weight. Choosing watt shows your raw power output which will depend not only on the intensity of your training, but also on your age, sex, and fitness level. Power in percent of FTP tries to equalise this difference so you can compare with others. In many ways, it is similar to showing your heart rate in percent of your maximum heart rate. Watt in percent of FTP is also what we use to calculate your training zones. Finally, watt/weight is used by many experienced riders since this is ultimately what determines how fast you can go on the road.
When you have power in focus on the recording screen (i.e., it will show as the big number in the lower part of the recording screen), simply tap the field showing your current power reading. You can choose to have your power shown either in watts, % of your FTP, or as watt/weight. You can set your FTP and weight under Profile.
Follow these links to read more on power, FTP, and watt/weight. You can adjust your FTP value under your Profile.