DSL.cz - Měření rychlosti is a free Android application developed by ASPA a.s. that offers Czech users a way to test the speed of their internet connection. This app helps to map the actual speed of mobile data networks in the Czech Republic and is considered one of the most accurate speed tests available. Along with measuring the download and upload speeds, it also provides a view of the measurement map of the entire country, allowing users to check for quality coverage. This feature can be found in the standard menu, along with a measurement history. Additionally, it is optimized for weaker phones, making it accessible to a wider range of users.