Bike satnavs are not going to be cheap. Garmin and tom tom being the favourites. I'm old school so i have a camera to take piccies, a phone to make calls and text and a satnav to well satnav. The advantage of the satnav is waterproof, comes with the bike, and car, holders. the screen is glove friendly so you can make changes on the fly. disadvantage cost the advantage of phones cheap apps. disadvantages, need to buy waterproof case, unless it is one of the newer waterproof phones. Some phone touch screen do not work with gloves. Also if you use google maps live beware of data downloads, use a dedicated off line app. Why not go the phone route and if it does not give you what you want then save for a Satnav.