FitBit

Many diligent people will check the "problems" of a product before spending their hard earned cash, one way is to check the product forums to see what problems current users are having.
However, be warned that anyone visiting the Fitbit "community forum" will only see one side of the story. Please understand that the comments placed there are under extreme censorship with total bias toward the positives.
If a user so much as posts one honest word about their incredibly unreliable products then the post will be deleted and if you continue to do your best to make honest answers to other people also suffering the same issues then you will be banned. Happened to me today.
I have also spoken to many other members that have had their posts deleted or have also been banned. Do yourself a favor and buy any other product except a Fitbit.
My suggestion is to read through the several hundred reviews here and on other non-affiliated websites to find out how poor their products and especially their customer service is.
Their mods are utter fascists that want to stamp out honest opinions.

Be warned.

I see now why the reviews are so terrible. I spent $200 on a fitbit blaze and after 2 months it stopped doing what it advertised. It doesnt hold a charge for more than 3 days, the step count is way off and it takes a solid 4 minutes to sync. I called and complained and after numerous emails back and forth they finally agreed to send me a replacement one and guess what? The "new replacement" is not syncing at all! I have uninstalled and reinstalled the app and still nothing! It also dies after 2 1/2 days and I dont use the notifications from my phone or keep the all day sync on. Piece of garbage and a complete rip off. Don't get reeled in by the name. There are many competitors worth looking in to.

I purchased a Fitbit Versa Lite from Fitbit.com on October 2nd 2019 it lasted a little over 2 months before all functions weren't working. I contacted Fitbit customer service and after their help and 4 calls nothing worked at all, it wouldn't even turn on or at least keep time. Then after 4 days they finally agreed to replace the watch, now I am at their mercy for getting a replacement which may or may not happen till the Dec. 27,2019. This started on Dec. 13,2019. Before the Versa Lite I had a Fitbit Charge, the first one lasted under a year, they replaced it and the replacement only lasted a little over a year. They poor customer service and products don't seem to last. I will not ever purchase anything from Fitbit again. I will spend a little bit more and get a more reliable product.

I had purchased my Fitbit HR through Amazon India. Unfortunately fitbit spoiled hence I sent email to Fitbit along with the photos of Fitbit. I got immediate response of my email and they agreed to replace my Fitbit HR. And they did it too but unfortunately that device did not work hence i sent them email again and finally they gave me FITBIT Charge 2. I received it today and did setting of its and working well.
Its never happened with Indian company in replacement device but Fitbit did it without any hassle.
Thanks to Fitbit

Purchased my Fitbit watch for a secondary reason to use it for Fitbit pay. Fitbit websites specifically indicates that American Express is supported but their app will not allow one to upload the American Express card. Numerous attempts to rectify this problem have gone unanswered by an atrocious customer service department. Since Fitbit is now owned by Google, one would think that a fixed to this problem should be readily available since Google pay excepts American Express, why can't they are smartwatch brand also accept it. More importantly, why can't they are customer service react and respond to problems with their app. Extremely frustrating and definitely a reason not to purchase their products.

Ordered fitbit 4
Arrived and immediately had a battery life issue. Called their tech and said GPS was on... Never turned it on.
Battery life 19 hours. Called again. GPS on. Never turned on.
Called again and had me reset.
Called 4th time... You are right, you have a battery issue. Return. Sent Fedex label.
Just called again, it takes 10 days for return. Due to Covid. But you will receive your new fitbit in 4 daays Fedex...
But first you need to receive an email from us with your address. Never would have sent new fitbit 4 without email with address unless I called.
Needless to say, very disappointed..

This product is only compatible with at most 10 android phones. Unless you have those phones you cannot buy this product.

I have moto G5s plus, turns out this device is only compatible with moto g5s. With one plus this device is only compatible with one plus 6.

If you have lower versions of phones which are already obsolete by the way, only then you buy this product.

Raised complaint to customer support, they told be to change my phone and then try syncing.

I was forced to give up my Ionic Fitbit that worked perfectly, and unfortunately I replaced it with the Fitbit Sense. Nothing but trouble has ensued: The Heart Rate is consistently off, the Sleep tracker is sporadic at best, and the sp02 oxygen sensor never works. Fitbit/Google knows these watches are junk, yet they fail to provide support and correct the bugs. I'm turning off my Fitbit account and will NEVER buy from them again.