Iot poster presentation topics

Suggest me some IoT poster presentation topics.

TOPIC: Finding the water content/moisture content using Bolt IoT module.
WHY THIS TOPIC: As we all know that water content is very important for any structural design.

In soil Mechanics Water Content (w) = Weight of water /weight of **Soil. take 0.9 Kg of dry Soil and add water about 1 liter (in volume) which is about 1Kg in weight. Mud or slurry tends to have water content more than 100%. Water content shows the weight of water with respect to that substance in dry condition.