Why are people throwing away their Fitbits?

Many Fitbit users have threatened to switch to other wearables instead - including smart watches made by rivals Apple and Garmin. Photo / Getty Images

If Twitter is anything to go by, the last steps measured by many Fitbits over the past week were taken to the fitness trackers' final resting place — the bin.

Unhappy Fitbit users announced they were ditching the devices over privacy concerns following Google's purchase of the activity tracking firm on November 1.

San Francisco-based Fitbit Inc, which boasts 28 million worldwide users, was purchased for NZ$4.2 billion.

In response, many Fitbit users threatened to switch to other wearables instead — including smart watches made by rivals Apple and Garmin.

"It seems impossible, but #Google is about to increase its obscene #surveillance program dramatically," wrote Robert Epstein of the American Institute for Behavioural Research and Technology.

Both Fitbit and Google have been quick to respond to the negative reactions of concerned users. Photo / Getty Images

"It's buying #Fitbit to monitor our sleep, activity, exercise, heart rate & more. Fitbit doesn't use such info to manipulate us; Google will. #BeAfraid."

"My @Fitbit will go in the bin — who owns @Garmin?" replied Twitter user Janet Duffy.

Meanwhile, Claire Alexander wrote: "My @Fitbit Charge3 is now In the bin. Data/account deletion request made."

"Do you really think your UK customers #trust or will accept @Google FFS, seriously!" wrote another.

And another shared: "Let's see how the #EUdata position unfolds... #applewatch here I come".

Both Fitbit and Google have been quick to respond to the negative reactions of these users.

"Strong privacy and security guidelines have been part of Fitbit's DNA since day one, and this will not change," said Fitbit co-founder and CEO James Park.

"The company never sells personal information and Fitbit health and wellness data will not be used for Google ads."