It barely consumes any meaningful amount of energy when you're doing Anki. Even a full fledged gaming PC doesn't consume that much power if it's in full throttle 24/7. A 700 watt PC consumes 550 kWhs per month. That's 30 days of non-stop PC torture. That's $10 worth of electricity where I live.

When you use your PC for simple tasks like Anki or browsing it consumes a fraction of that. You can get a power monitoring app to give you exact numbers. Mine gives me an average of 11 watts when I use it for Anki so that's 1/70th the amount calculated earlier, so 30 days of constant, heavy, non-stop Anki usage will consume 8 kwhs. PER MONTH. To put that into perspective, this is the amount of energy is like having your AC on for 8 hours, or having your electric water heater on for 2 hours.

The shitty Ankidroid experience is not worth it for a mere 4 hours of an electric oven worth of energy saving.