Mapbox has an excellent alternative map platform based largely but not entirely on OpenStreetMap data. Mapbox GL JS in particular is a joy to work with and extend. https://www.mapbox.com/
It's not free, but it's very easy to use and the pricing is roughly 1/10th of Google's when you get past the free tier: https://www.mapbox.com/pricing/
Mapzen used to be an alternative but sadly they shut down. However many of their products live on in open source or paid-hosted alternatives. See https://www.nextzen.org/ for a start.
It's not free, but it's very easy to use and the pricing is roughly 1/10th of Google's when you get past the free tier: https://www.mapbox.com/pricing/
Mapzen used to be an alternative but sadly they shut down. However many of their products live on in open source or paid-hosted alternatives. See https://www.nextzen.org/ for a start.