You can use OruxMaps for your outdoor activities. It is an online and offline map viewer. With this application, you can use different map formats, such as GeoPDF from the USGS store, GeoTIFF, .ozf2, .img garmin maps (vector, no full support is provided), .mbtiles and others.
Supported Android
{4.0 and UP}
Supported Android Version:-
Jelly Bean(4.1–4.3.1)- KitKat (4.4–4.4.4)- Lollipop (5.0–5.0.2) – Marshmallow (6.0 – 6.0.1) – Nougat (7.0 – 7.1.1) – Oreo (8.0-8.1) – Pie (9.0)

Download OruxMaps GP 8.1.8GP Patched APK For Android

OruxMaps_GP-v8.1.8GP_build_801080-Mod-armeabi-v7a.apk