WiFi Thermostats - any good budget options?

Looking to control a four zone residential home heating system using WiFi enabled wall mounted thermostats.

Have looked at offerings from Honeywell, NEST and the like. Amazon, ebay, and the big box home improvement stores all have the same limited choices. Hoping you tech-oriented budget minded folks might have a silver bullet.

Trying to justify the spend considering a quad core processor tablet with a touch screen running Android OS costs $60. Yet a simple WiFi thermostat electronic switch costs $200?

Anyone using a WiFi thermostat brand or model that could recommend it? Or anyone find a source for these at a reasonable price? Need four of them and hoping to sidestep a big expense.

This one has the most functionality at the best price I can find so far. Still digging. Any input is appreciated.

Aliexpress Touch Screen WiFi Room Thermostat

That certainly looks nice, but the description indicates WIFI is optional and doesn’t mention what type of control is available, browser based only or android app. I have a Filtrete 3m50 that has worked quite well for a couple of years, though I had to have them replace the WIFI module under warranty. http://www.radiothermostat.com/filtrete/products/3M-50/