Mistake 1: Do not give everyone your home address

One of the simplest and not even IT-related problems is: You give your home address to so many different institutions.

Now why is that an issue?

Because they will send you spam via post mail?

Certainly not. That rarely happens these days and it is not a real danger.

The big problem with leaving your home address in every hotel, restaurant for a COVID check-in and so on is that your home address is often used for authenticating you when you call the tax office, your insurance company and others.

If somebody knows the name of your health insurance company, your name, your membership number (which can be easily obtained from your insurance card) and your postal code they can call your the insurance company and ask them about the most private things about your medical history.

That is already quite painful. But it goes on.

They can then use that information to build a profile about you and impersonate you and steal more data about you.

Now there are some institutions which will require your home address for various reasons. If you order food online to your home, it's not possible to give them a different address. Your bank will often also insist on having your home address.

But you might leave your home address in so many places where it is not absolutely necessary, like in a hotel, or a restaurant or some membership program that is not properly secured.

Sure, Uber Eats or whatever you use could get hacked and so can your bank. But hotels, restaurants, membership programs and similar businesses tend to have lower standards for IT security. Remember how Marriott's program got hacked a few years back?

By exposing your home address to so many different databases with a lower security level, you are increasing your risk by a few times vs. only giving your home address in cases where it is absolutely unavoidable.

Mistake 2: Using an old phone

It's sad for the environment, but it's true: Most old phones do not get software updates.

Since software is a constant cat and mouse game, no old software is ever safe.

Ergo, old phones are pretty much automatically unsafe.

The risks of having and old Android phone (Samsung, LG, Huawei etc.) tend to be slightly higher than with an Apple iPhone, but mostly because Apple, on average, supports older hardware than most Android manufacturers.

But be it Android or iOS, if your phone is more than 5 years old, you are often out of luck.

You will not get the latest OS updates and therefore your phone can be hacked easily in many cases.

In most cases, the only solution is to get a new phone which supports the latest and safest operation system version.

Mistake 3: Not updating your OS and important software

Another big mistake is that many people treat software updates as if they were installing the latest optional bells and whistles to their computer, or in other words, as if you could wait a few more weeks to install them.

Unfortunately, that is not even completely untrue. Software updates often do come with more bells and whistles, which can cause issues with your existing software, slow down your device and so on.

The other side of the problem is: Security fixes these days do not come separate in many cases.

Very often, you can't just simply get that security critical issue fixed without updating to the latest OS version. There are of course exceptions, but installing bug fixes and work arounds to older versions is becoming more and more of a niche thing each year that only the pros can do, not the average user.

For mobile phones, it typically makes sense to update to the latest OS version of iOS or Android within two weeks, all the time.