This can be used as a practice mirror too:

https://www.sharperimage.com/si/view/pro......1?trail=

One type of mirror that I use a great deal during practice sessions is an automotive convex mirror. I position one at a tough angle that a spectator may be viewing from, so I can see what the spectator would see. Flat mirrors aren't the best for angle work, in my experience, but are fine for most practice sessions.

Nice mirror but a bit expensive I think

I still recommend using video to study routines in addition to a mirror. The “Blink Syndrome” was something I was taught many years ago and describes a magician’s desire to be fooled to the extent that they will unconsciously “Blink” at the exact moment a sleight is done. It allows you to potentially fool yourself in a mirror but not to the unblinking eye of a video camera.

I'm always fighting against that blink syndrome haha, video is definitely a good technique to use, but doesn't allow you to make adjustments in the moment if you're flashing at certain angles.
I found a cheap 3-way mirror on one of those wholesale china sites for $13 that does the trick, Neznarf's link is pretty, but horribly overpriced.

I agree with you both. I like having a mirror in front of me when working on a new move or something I know I’m not even close on yet. Than I like to record my self and watch it back for fine tuning and getting something I’m decent at to where it’s as perfect as I can. I picked up Sean Yang's 3 way mirror it’s coasts little more than id like but not too bad it was about $30 USD (peanuts compared to the first one listed above) it uses non glass mirrors so you can take it with you and not worry about them breaking and when folded can function as a close up pad. For recording my self I picked up a small flexible arm tripod for my cell phone that came with a Bluetooth remote for under $15 USD. Another thing to be mindful about and why a recording is good is if you become to a custom to watching your self in the mirror it can throw you off when it’s not there. For that reason I use the rear camera on phone & try to look up at it as if it where a person I was showing magic to. The rear camera is better anyway, I get used to not watching my hands, and I get to see it as my audience would.

The "Blink" (point of indication) was discussed on an old Vhs Tape I have from Vito Lupo.
I purchased Sean Yang's 3-Way Mirror (both mirror and close-up pad) from Penguin a few years ago.