Fastah 4G Finder - Fastah 4G Finder app contains features through which you can access a color map to get an idea about the speed of the internet on your current network.
Cell Signal Monitor - Cell Signal Monitor is an advanced network monitor that helps you to watch the state of cellular network by gathering data about cell towers. The app supports GSM, UMTS and LTE networks. There is a Free edition with adds.
NetMonitor Cell Signal Logging - NetMonitor Cell Signal Logging app helps you in receiving accurate measurements of the speed of the internet and the strength of signals to choose the correct network according to your needs.