When should I use a flex goal?
Flex goals provide the most configuration possibilities. It's best to use a flex goal whenever you need a specific target, or if you want to record what you get done in partials steps.
Here's an example: You set a weekly target of 20 kilometers and you manage 5 kilometers four times per week – goal accomplished. Just make sure that you record every run. Goalify calculates your daily or weekly overall achievement automatically. No need to do that in your head. Maybe you want to drink two liters of water every day. Just record every glass that you drink and at the end of the day, you'll have reached your goal.
You can also set specific goals for every day of the week. This option is best suited for creating detailed training plans.