Here is a monocular that doubles as a microphone for your smartphone with an accessory. The PENTAX VM 6×21 WP Monocular has an ergonomic design and can withstand exposure to water. It has 6x magnification and minimum focus distance of 70cm.
You can easily handle this monocular with one hand. It has a rubber coated body, multi-coated lens, and a tripod screw for easy mounting. It can capture images with your smartphone thanks to the V-SA1 adapter. You can also use this as a 18x microscope.