The network speed measured by the app is too low. What's wrong?
The speed corresponds to the slowest element in your network - if your Internet is the bottleneck in your network setup, it will be the Internet. But it can easily be your modem, router, and also phone or tablet (older devices aren't fast enough to handle fast Internet connections).
- 802.11b - ~5Mbps
- 802.11g - ~25Mbps
- 802.11n - ~75Mbps
- 802.11ac - ~450Mbps (can vary depending on the exact configuration)
This means that if you have a 802.11b/g wifi router and a 40Mbps Internet connection, your router will be the bottleneck that limits your connection to 20Mbps over wifi. (So either buy a better router or get slower Internet connection and save some money on your bills.)
For more details about what speeds to expect from Wi-Fi, check this (very good) resource: