Strava is pretty much the universal cycling app. Even if you don't use the social networking aspect of it now, you might eventually. And you can keep your rides and routes private.

The advantage to Strava is the huge database of publicly accessible rides by others in your area. Helps in choosing routes. And you can compare your rides against others to get a rough gauge of conditioning.

I emphasize "rough gauge of conditioning", because, besides age, factors include:

• Bike weight and design -- while Strava can estimate power output based on these factors, I'm not sure whether it offers something like a golf handicap or other system to calculate relative performance.
• Wind. Huge factor in some areas and times of year. Again, I'm not sure Strava offers any way to compare the effects of wind.

For the first year I rode, after 30 years away from cycling, I only used Cyclemeter and Wahoo Fitness to evaluate my rides relative to my own performance. But as I got involved in local casual group rides I began to get more interested in Strava because I saw how friends were progressing as well. And keeping track of much stronger riders on the same routes I ride gives me a more realistic sense of things. Rather than feeling discouraged that I'll never approach that kind of speed or fitness, I'm contented with the progress I am making.