Here’s a comprehensive guide on what to do to protect your privacy with each of the virtual assistants.

How to curtail Alexa data shared with Amazon

Among smart assistants, Alexa has the most comprehensive and straightforward set of privacy controls. Amazon recently released the Alexa privacy hub, which has a thorough explanation of the types of data collected by the virtual assistant and how to change its privacy settings.

Here’s how to opt out of human vetting:

Open the Alexa app on your smartphone and tap Settings and then select Alexa Privacy .

Tap Manage How Your Data Improves Alexa .

For the control that says Help Improve Amazon Services and Develop New Features, toggle the switch to the off position.

Here’s how to delete your voice recordings:

In the same Alexa Privacy menu, select Review Voice History .

In date range, select the time frame of recordings you want to delete, such as All History .

Tap Delete All Recordings for All History.

Here are other precautions to take with microphones and cameras:

Alexa devices include a physical button to disable their microphones. Hit the kill switch whenever you are having sensitive conversations. The device will illuminate with a red light to indicate that the microphone is off.

Some Alexa devices, like the Echo Spot alarm clock, have a built-in camera. The easiest way to disable it is to say, “Alexa, turn the camera off.” If you still feel uncomfortable with the camera, consider buying a cheap webcam cover that can slide over the lens.

Amazon said in a statement that it takes customer privacy seriously. “We continuously review our practices and procedures to ensure we’re providing customers with the best experiences and privacy choices,” the company said.

How to delete your Apple Siri recordings

Siri is the most lacking in privacy controls among the virtual assistants, and the process to manage user data is the least straightforward.

For example, Apple does not offer an option to let people opt in to its so-called grading program, though it has said it plans to do so in a future software update. In addition, there is no ability to review Siri recordings associated with your account, and deleting recordings is cumbersome.

Siri does take some steps to mask your identity. When you make requests with an iPhone, for example, the device associates those with a random identifier instead of your Apple account ID, according to the company. To reset that random identifier, you can turn off Siri and then turn it back on.

Disabling Siri will also delete your data associated with it, including recordings.

Here’s how to disable Siri on an iPhone to erase your data and reset your identifier:

Open the Settings app, then tap General , then Keyboards . In the Enable Dictation control, switch it to the off position.

Return to the Settings app. Select Siri & Search . Then disable the switches for Listen for “Hey Siri” and Press Side Button for Siri . You will then see a message asking if you want to disable Siri, which will remove your data from Apple’s servers. Tap Turn Off Siri and your Siri history will be deleted.

To re-enable Siri, go back to each of those settings and turn them back on.

Some of the sensitive recordings uploaded to Siri appeared to have come from unintentional activations, like when the crown of the Apple Watch was pressed down by accident, which summoned the assistant. (In my experience, this can happen when leaning a hand against a couch cushion.)