Navigating Duolingo is dead simple. Do the next lesson. You sometimes get a choice of two or three ones to do next, but it's all laid out visible on a tree, with opportunities to attempt to test out at intervals. Babbel has a straight line "Beginner's Course" but it also has pick-and-choose sections as well, and it isn't obvious, the way it is with Duolingo, how much you have left before you've done all of it. Babbel paid to have actual humans speak the words, vs. Duolingo's robot. Because I have a real live instructor to talk to at fairly frequent if not perfectly regular intervals, I've turned off the use-the-microphone feature on both of them. I'm doing these lessons with kids and/or husband in the room a lot and it's irritating enough already.
They both have a mix of pictures, translating exercises. Babbel has extensive, in line grammatical explanations. If you want that in Duolingo, you go dig around in the comments. (Crowd sourced grammatical explanations are about as good as you would expect them to be.) I don't like doing Duolingo on my phone, because I run into fat finger errors. I discovered I really _liked_ Duolingo on the laptop, because I type fast and relatively accurately. So I've been trying to do Babbel on the laptop (I used to use the iPad for this more often in the past) and I'm running into all kinds of problems because of the way the type-in boxes handle editing and cursor positioning. It is somehow NEVER what I expect it to be. If they fixed that, I would probably really love Babbel. As it is, it's going to take me a while to adapt.
Rather than go through _another_ start from the beginning and go through everything (these are getting painful) Dutch course, I'm going through the grammar specific stuff, in hopes that it will clear up some persistent confusion I have with open/closed syllables and vowels, and some of the verb tenses. I also seem to have some difficult to characterize word order issues when there are adverbs, objects and negation. Maybe some extra sentence building practice will help with those.