An Android usually has to be recharged more often than the equivalent i{hone being used the same way.
Other than that, it takes a little getting used to the differences (as you probably know from your Samsung).
Some people are glad they switched, some say they're switching back because they can't stand something about Android. So look at how the iPhone works, look at how the Samsung works (including your fitness apps - if you don't have any on it, go to the Play Store with it and install them) ... then you have to decide for yourself. The S8 will probably run a bit faster than an older tablet. (One thing to be careful of - the S8 is water-resistant, not waterproof. It can take being wet, but it usually can't take being plunged into water, or splashing around in even a few inches of water.)