The connection is only for downloading routes from their cloud, sync activities, unit settings, etc…. In a ride, it does not need a connection unless you are using its live tracking. Then that can be via a SIM if you install one or via a phone as hotspot wifi. If you were to sideload other apps (it’s easy with the android tools) then you may need live data if, say, you had a weather radar app. Wifi through hotspot is not a terrible power consumer but is pretty snappy over LTE and is typically less than cellular in most cases.

you can drop a pin on the map and the Karoo will route to it. You can also route to a POI. You can route home or back to the start. Very easy to change a route while riding. Their dashboard runs extremely well on a phone browser and is actually best in class for device mobile route creation but you do need connectivity and syncing is super fast.

you do not need an internet connection to ride. In fact you can be in airplane mode. I never connect my phone while riding and my Karoo is almost never connected to the internet while riding.

however, once the ride is ended and at the first possible internet connection opportunity, the device instantly syncs and will sync with many of the online services - RWGPS, Strava, Training Peaks, Xert, etc…

With a paired BT speaker you also can get audio turn by turn directions. This, in an urban or suburban environment or in traffic, is a safety game changer.

Varia implementation is best in class over even Garmin.

it will control ANT+ lights. I use the Trek/Bontrager Flare/Ion pair.

maps are top end if not best in class and getting better all the time. Display is best in class and screen operates with the speed, control and alacrity of a smartphone screen.

all functions and operation can be accomplished by using buttons alone as well as touchscreen gestures (both provide complete control). I find this invaluable when riding in the winter.

the mount is terrific. There are compatible inserts available for K-edge and other mounts. Close the Gap will have theirs out in less than a month they tell me.

Strava and RWGPS starred routes sync automatically. RWGPS is exceptional especially for shared routes. Strava Live segments are also supported - I don’t use them - but many have said it’s a best in class implementation.

that said, it’s a bike computer with all that goes with that - it’s a tough environment with rf sensors. Karoo handles the environment as well as the best and better than most but normal caveats with that uniqueness still apply.

I like mine. It’s all my wife and I use now. Shared routes via RWGPS are amazing. I make a change and she syncs and the changed ride is there automatically.