Angle Finder fo Canon 6D
If you are getting glare issues with field shooting, then you need a device that will operate in the bright daylight (we use Panasonic Toughbooks for field use but I wouldn't recommend it because of the high price). Needless to say, they work OK indoors but they do well in the bright sun of Nevada (Toughbooks are used by the field crews for the power company). This is something I have not had any issue with. It's possible that if you use your smart phone, you could get a device that will allow you to shade the screen enough to see the image. My iPhone 5s doesn't have a lot of problems with viewing in the sun. I haven't noticed any issues indoors or outdoors.