Twitter has finally introduced support for 4K photos on both its iOS and Android platforms, which has been one of the updates revealed for some time. Users can also upload and display photos in higher quality up to 4K. You will, however, need to manually activate the option in the settings to enable this, just follow these simple steps:
To get started, go to “Settings and privacy” then choose “Data usage” and then select “High-quality images” here you can choose which network is used for images high-quality images loading on Twitter whether you can select “On cellular or Wi-Fi” or just “Only on Wi-Fi”.
To enable high-quality or 4K image uploads, make sure you have updated your Twitter app via App Store or Google Play Store. After you update your Twitter app the go-to “Settings and privacy” then choose “Data usage” and select “High-quality image uploads” here you can select which network should use for high-quality or 4K images upload by choosing “On cellular or Wi-Fi” or just “Only on Wi-Fi”.

Source: Twitter