Apache is a free and open-source cross-platform web server software.
Firebase is a Google-backed application development software that enables developers to develop iOS, Android and Web apps.
Google Maps is a web mapping service. It offers satellite imagery, aerial photography, street maps, 360° interactive panoramic views of streets, real-time traffic conditions, and route planning for traveling by foot, car, bicycle and air, or public transportation.
OpenLayers is an open-source JavaScript library for displaying map data in web browser.