I am overwhelmed by the many tips received, thank you all. Unfortunately, I lack the time to test all the suggested apps but as I promised to give feedback, here it is:
RELIVE
I chose it for a full test because of the many recommendations but also because I found, that Efren Gonzales uses it; a good reference.
The app is relatively intuitive to use. The basic free-of-charge version is very plain and the limitations are frustrating, for instance, there is only one background music available, you want more, you pay. Same for many other features that soon become desirable, once you use the app. They offer a monthly fee of a reasonable 3 €, which can be canceled anytime. Along with the current free trial of one month, this should well cover a full Camino including self-training before- and editing after the walk.
I have not tested all the features but judging the free version, they are well thought.
I will choose Relive for the purpose of giving my friends the possibility to follow my Camino, because of its simplicity and also because I will record my Camino in parallel on video, in which I'll invest some ambition. Relive can be integrated therein in a useful way.
FINDPENGUINE
This app has many more features and enables to do complex recording of journeys.
Recomendable for ambitious Peregrinos, this app replaces all other diaries and videos. After a day or two of self-training, it offers entertaining results that will impress your friends.
IRRITATING
Both apps keep on sending spam mail after downloading, sometimes several per day. And of course, both try hard to get a direct link to your wallet.
Buen Camino