Sygic Travel Maps might be a bit more popular than PARI/GP. We know about 1 link to it since March 2021 and only 1 link to PARI/GP. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
This is one I'm aware of, I don't have any previous experience with it though. https://pari.math.u-bordeaux.fr/. Source: about 1 year ago
I've been using Sygic Travel from the Czech Republic and really like it. It doesn't use Google Maps, but you just press the location on the map, click add, then it autosorts to give you an optimized itinerary (like yours does) and spits out the itinerary. I think your biggest issue is being cost competitive. I paid $7.99 once for Sygic Premium (I think it's $9.99 now), so $19.99/month is an entire tier higher in... Source: almost 2 years ago
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