Tbh, I didn't like any of the meditation choices included in the Fabulous app – I found that there was far too much of the voice over instructions throughout the duration of your routine, and constantly interrupting you while you tried to, well, meditate.
But to answer your question, I like to meditate, or have my quiet time, the first thing in the morning, as soon as I wake up. I am an early riser, so I don't feel rushed to be somewhere else when I am meditating. I found it also helps to start with a couple of minutes of breathing exercises (the ones in the app will do) to relax your body and get prepare you for the meditation.
I've always struggled with just meditation, but teaming it with yoga has done wonders. After a long or short workout/stretch your body is relazed enough to open your mind up to meditation.
Breathing, it doesn't matter where you are, just get sit down, close your eyes and for 5 min. start to concentrate in your breathing ( set a timer to don't concern about the time)
For me, it is best to do my meditation before I get out of bed in the morning. I can also do it other times during the day, but if I do it first thing then I am more likely to do it. Also, right before falling asleep. It helps me relax and clear my head.
Doing meditation at certain places in my routines helps me to meditate every day. And with it planned more then once if I miss it one of the times I will be more likely to get it done at least once.