The use of ultra-small unmanned aerial vehicles (UAVs) as a carrying platform for remote sensors for agricultural use has attracted increased interest during the past years. In contrast to other common carrying platforms, UAVs are inexpensive and flexible. However, while ultra-small UAVs are inexpensive, costs of remote sensors vary considerably in the range from below 0.5 times the cost of a UAV to 24 times the cost of a typical UAV depending on the technology. This makes the correct choice of the remote sensing technology crucial for successful and cost effective operation of UAV based remote sensors in agriculture. In this work, we summarize agricultural demand and UAV carrying capabilities. Then, we provide overview on existing remote sensing technologies. Finally, we will compare the technologies based on the UAV capabilities and agricultural demand providing recommendations for sensing technology selection. ; internal