Depending on voltage and amperage of what you are switching you can use a relay connected to a Raspberry Pi (minicomputer) Here are a couple random youtubes showing the concept. You would need to size components appropriately for your load. https://www.youtube.com/watch?v=8cPK8lh6oLI&t=2s https://www.youtube.com/watch?v=mj2kMD0LCR4 There are also some wireless outlet plugs with key FOBS again need to consider amperage of loads. https://www.amazon.com/NEWNEWLIU-Wireless-Waterproof-Electrical-Equipment/dp/B0FR9DWTMR Wireless that can also be used as timers. May be able to couple with a relay for heavier loads. https://www.amazon.com/HBN-Grounded-Wireless-Compatible-Assistant/dp/B08157D9GK Just some random ideas hope this helps please follow up if you find a solution. | 
Looking for a relay that can be turned on through wifi
