I have been looking into this recently and have not much luck. The ideal kit for me would be fully wireless, app-based and be able to recharge through solar. Unfortunately everything I have seen seems to score poorly on at least one of those.
From what I can tell, the most effective solutions seem to be those that have power fed from the rear lighting, and have a dedicated wireless monitor that you can mount on the dash/windscreen - which is a little too intrusive for me.