In the past I was working on different plugins to connect with multiple APIs and use their isochrone endpoints in QGIS. Let me summarize some of my findings and share my opinion on HERE, Azure Maps, Bing Maps, ORS, Esri and Iso4App.
The OSM based QuickOSM plugin offers a great way to download some data from OSM. As an alternative I am developing HQGIS which offers an easy way to get geocoded addresses, routes, isochrones and POIs for your everyday work based on the HERE API and the HERE datasets. Now the plugin offers support for the processing toolbox as well. Follow me on a short insight into POI search around desired addresses.