Basicly, Walkie talkie is same like Handy Talky, they are two ways radio communication device with half-duplex system. Both of them same using radio frequency to send message, meanwhile Push to talk use provided GSM network. The difference is on the their advantages like this:
Overall, the weakness of two ways commercials radio has explained above, whether walkie talkie or handy talky. But, for the details will be explained below:

Limited Coverage
This is the main weakness of walkie talkie and handy talky. They have limited coverage range because the radio frequency can’t connecting ih long range. The solve of this problem is build a repeater to increase the range of coverage. But, build a repeater is so expensive. It different with Push To Talk, it have use GSM network that have been spreading around the world.

Inefficient Channel
Channel in radio commucation is very important. with channel, everyone can receive a same command in one group. Walkie talkie’s limited channel will be a problem for a great company with several personel. This is would be a serious problem if the company need many coordination to many channel. Push to talk have unlimited channel features. You can made channel as many you need. This feature is provided in Poosh, where the channel could be made as many as you need on the field.

Additional Features
Both walkie talkie, handy talky or push to talk have a realtime radio communication as their main feature. This adult jobs need additional feature like text messaging, picture or video messaging, video streaming, or even in oil and gas industries they need GPS features to know where is field personel location. Additional features that needed on the field have been provided by Poosh. Poosh can used for text, pictures, video messaging, or even live video streaming. Plus other additional features like GPS location, broadcasting, etc.

Management System
Management system is a central system that can control everything about radio communication. With this system you can do monitoring about everything you need. Walkie talkie and handy talky didn’t have this system because they can only do two ways radio communication, while push to talk as a profesional service, of course you must to have this features.