Flightaware is very limited. Jets at 35,000ft aren't really an issue. Small Planes, Hot Air Balloons, Light Sport Aircraft and other many other types of Private Planes flying VFR are not going to show up on an any App I'm aware of. Some have ADS-B due to recent regulations, but they don't kick in until January of 2020 and you would need some expensive hardware to track. There are also many exemptions. The good news is most are supposed to stay at > 1,000 ft AGL. Private Pilots are not required to file a flight plan with the FAA although its a good idea.
Another problem is Helicopters. They go pretty much where they what to and sometimes pretty low. For example, the local Hospital is 1 mile from me and has their Life Lion Turbojet Helicopter that responds to local emergencies and transports patients from A to B. I'm not aware of an app or software that you are requesting. I'm also a Pilot FYI.
Rules may be different in Canada? You guys also have lots of lakes with aircraft flying in/out as well. Personally IDK - never flew there - Private anyway.