4.6/5 Deducted 0.4 for the cumbersome download process; otherwise a 5-star navigation app.
Headline: Powerful offline navigation, but the download process needs patience
If you buy a GPS SD card from eBay/Amazon (pre-loaded with IGO World), skip the download headache entirely. Otherwise, clear 4–5 GB of space, use strong Wi-Fi, and expect a 45-minute setup.