Works well but you may need to attach it upside down to prevent weight of phone from pulling it off center
926485
I've been looking for a universal adapter of this sort for a while.  The clever design of the Carson HookUpz allows me to connect my phone without having to take it out of it's case and it will connect to my spotting scope or my binoculars.  If I get a new phone or a new scope, I can still use the same adapter.

I read the reviews carefully before ordering and had some concerns about the weight of the phone pulling the adapter off center.  These fears were well founded but I have found a work around.

The issue raised by several other people in their reviews is that the springs which clamp the adapter to the optics are not strong enough to counteract the weight of the phone.  I did indeed find this to be the case with my iPhone 6 but, after some experimentation I realized that clamping the phone upside down solves this issue on my angled spotting scope.  The puts the bulk of the weight above the lens.  The downside, off course, is that all of my pictures will be upside down but that's easy enough to fix in post processing.

Two other thoughts:

-- As mentioned, I have an iPhone 6.  My case is very slim, barely adding to the dimensions of the phone and it just fits in the adapter but it's tight.  If you have a bulkier case or any phone larger than the 6 it likely won't fit.
-- The carrying case is great but the adapter will not fit in the case with the height adjusted to fit my phone.  This means I need to readjust the height with every use.
2113189
This item works well for what it's designed to do (charge the phone).  I have a cover on my phone and it still is able to charge by removing the added plastic piece that is used to raise the platform up so the phone can sit on the base properly.  Unfortunately, if you have a cover, charging the phone without that extra plastic piece creates a rather "wobbly" feel when your insert the charging stem into the port on the phone.  Basically, the phone is balanced upright on the stem.  Though, the phone does rest against the back support of the base, so it doesn't put any added stress on the charging port or stem. I think the design could have been a little better, but it's certainly not the worst charger I've ever purchased.
78628
Here are the upsides of this Northward mobile phone holder. First, it's reasonably priced. Second, it mounts to a car dashboard or desk easily and the sticky bottom holds it securely. Finally, the mount comes ready to use and requires absolutely no assembly. (And it has a set of directions on how to mount your phone.) Because of these upsides I'm willing to give it four stars.

However, there are some downsides, which keep it from being a five-star product. Most importantly, although the arms are supposed to hold a phone securely, there's still a bit of wiggle. This won't be a problem if you use this as a desk mount. However, I'm not sure that this would be secure enough to hold the phone in the car, particularly if you were to have to brake or turn suddenly. Moreover, if you're planning on using it as a car mount, it isn't as versatile as are some car mounts. It is only a dashboard mount, which limits where you can place it in the car. Finally, each time you return the phone to the mount you're going to have to readjust the arms, since when not in use, the arms tend to revert to the horizontal position. This can be a hassle if you try doing this while driving.
3207501
I love the design and how this works. The only problem I had is it can be a little top heavy and when you make a slightly hard turn the phone kind of turns down. I was able to take a coat hanger and make a tie to the dashboard that keeps it in place. ( It does not look like a quick fix..  hehe  It acts as a stabilizer and keeps it from sliding down)
2134133
It's perfect for holding phones on its side. Still good for vertical just not perfect. Everything else I love!
2113751
It works, only thing I don't like is how the phone cable doesn't have a spot to keep it in place
1159486
Don't get this is if you have a bigger phone, it will tip over. I have to wedge things under my phone to keep it in place. Works really well if you have a smaller phone though
1637004
I really like this mount as it allows my phone to be rotated to an optimal position while mounted to the air vent in my car. My real issue is that the mount does not seem to grasp as securely to the vent as other mounts of this type. The phone is very stable in its attachment to the mount, but wobbles at the vent attachment. It feels as though my phone could easily drop if not held while moving on the mount.
3818284
I'm using this with an iPhone 6S Plus which is a pretty large phone. I can't adjust the vent to keep the phone where I want it because the vent won't hold the weight. When I attach my phone horizontally it holds very well because the bottom is braced by the dashboard. I don't trust using it vertically.

I did have it come off and drop my phone (the magnet was still attached) once so I've been careful to make sure it's pressed in firmly and haven't had it happen again. I wish the grip had little hooks to grab onto the louvers instead of just friction because it's too easy to pull out. I've also learned to rotate the phone instead of yanking it directly off because the magnet is very strong and it's too easy to pull it off the vent but if you rotate the phone, the holder stays attached to the vent.

I've used the Scosche with the sticky blue gell which works surprisingly well but I need to replace them after a year or two because the gell breaks down. I like the magnetic holder but you need to either attach the metal plate to the phone or put it in a case. I put mine in the case and it holds through the case very solidly.

I like attaching the phone to the vent because it's easy to see but not as distracting as my previous holder which was attached to the windshield. The attachment to the vent is pretty good but I wish it was even more secure so I wouldn't worry it would fall off. It's well made and once you get used to how you have to attach and detach your phone it works very well.
716464
Pretty good but I have a s3 and it seems to be too heavy for holder at most angles but when I find the right spot it works good.
2508299
There are some apps (mint.com for example) that do not support rotation. When you are holding the case normally with the top flap to your left as shown in one of the product pictures, these apps will be upside down! Easy enough to turn the kindle over but it still seems like a design flaw. I don't think there's a way to fix it though since this orientation is needed for the camera to be at the top when you prop up the Kindle in landscape mode. Just an interesting oddity...

Otherwise this case is sturdy and looks good. It will add a lot of thickness and bulk to your Kindle but I think this improves the grip. Also the leather areas on the side give me something to hold on to where I don't have to worry about accidentally turning a page while I'm reading (I've done that a lot before getting this case).

Overall, a good case for the price.
2198458
Works great, but the position that it must be placed in is not ideal (at least for my car). Magnet is strong so phone stays put and rarely falls off. Nice product but needs a better attachment piece so it can go into the venting ducts rather than the vent control.
4825145
Works well but have to be careful putting phone in charger as the plug is flexible and doesn't always go in,
I had to make a 'cage' around it to make it easier to use
2401508
Kind of loose. I put this on my son's bike so he can use this for his phone when he rides home from school instead of searching for his phone for any reason. Took a little time to install because once it was done I found it was sliding and didn't hold the phone in place even with the rubber pieces in place. I used zip ties in the end which works but without them ,the weight of the phone pulls the holder until the phone screen faces the ground. Other than that it is a good item to have.
1760161
Easy to install -- holds my iPhone 6S Plus securely; works well.  My only quibble is that when it's in the mount, the weight of the phone makes it tilt slightly forward from the top, which makes it a bit less than ideal if you're using the phone for GPS or Waze.  In a perfect world, the mount would be tight enough that you could angle the phone however you wanted and it would stay that way, but there's not a way to tighten it that I have found.  But it's not a huge issue; I can still see the phone reasonably well.  For the price, a very good product.
152519
work find,  the back phone cover bump up a bit, if the receiver thinner the cover should stay flat..nicer
2221929
This car mount works well. It holds my Galaxy S7 in place. The problem is putting it in the mount and taking it out is kind of difficult. The grip on the phone is very strong, so you have to really pull it open to put the phone in the mount. When you're removing it, you can't just pull the phone out because the vent clip isn't strong enough to stay in place, so the whole mount will come off with the phone. You have to hold the mount in place and then remove your phone. Despite this inconvenience, the mount is exactly what I wanted. It's slim, so it doesn't block the air vent. It's position-able, so I can aim it directly at me. It's secure, so it won't fall off while I'm driving. And it doesn't require a magnetic plate or anything else to be kept on the phone.
Pros:
Secure
Slim Design - doesn't block vent
Can position for best viewing
Doesn't require special case or metal plates on phone
Cons:
Difficult to put phone in and take out

I received this product at a discount in exchange for my honest review.