If you are using Android 7.1.1 or earlier, you will no longer be able to visit multiple websites as of 2021. This is due to HTTPS and more precisely to the certificates from Let’s Encrypt.
The HTTPS protocol (instead of HTTP) is used to encrypt communications. Also, you can be sure that you are seeing the good content of the websites. Sites on HTTPS (like KultureGeek) must use a certificate issued by a third party. One of the main players in this area is Let’s Encrypt. Its advantage is that it is free, hence significant acceptance by the websites. But it will get stuck with Android 7.1.1 and earlier versions in 2021.
When Let’s Encrypt was launched, it required that its own root certificate (ISRG Root X1) be included in all browsers and operating systems. At the same time, the certificates issued were signed by the IdenTrust DST Root X3 certificate. It’s been around for years in Windows, macOS, Android, and other operating systems.
Let’s Encrypt has an agreement with IdenTrust and will expire on September 1, 2021. The group announces that they do not intend to renew it. As a result, all operating systems that do not have the Let’s Encrypt root certificate will deadlock. They can no longer access websites and services that use their certificates for their HTTPS connections.
In other words, Android 7.1.1 and earlier versions will no longer trust certificates from Let’s Encrypt from September 2021. Therefore, connection to websites is not allowed.
What if you have an old Android smartphone?
There is a solution: use Firefox. Mozilla’s browser uses its own certificate store and supports ISRG Root X1. The sites with the Let’s Encrypt certificate can therefore function normally. But it will still get stuck with other apps.