You can contribute by supporting projects which reduce carbon emissions with reforestation or renewable energy.

Often times it's more sustainable to go into the store or restaurant or pick up the item or food yourself. You will avoid unnecessary packaging and potentially transportation emission from delivery. This depends obviously on distance and type of transportation you would use, since otherwise delivery can be actually more efficient, especially when the providers is running on electric mobility and multiple deliveries are carried.

Next time if you need to get a new phone case get a biodegrade phone case. Some are made of bamboo or plant based materials. The usual plastic in cases is a huge waste.

If your phone is working and in good condition you can make a positive contribution by donating or selling it so someone can use it and doesn't have to buy a new phone. If it's broken try to have it repaired or give it to a mobile shop that will properly recycle it for you.

In airplane mode your phone will charge faster because radio frequencies are turned off and your phone will charge faster.

Avoid letting your phone plugged all night which consumes more energy and increases the risk of fire.

Good maintenance usually equals efficiency in regards of the things you own. Care for your appliances and they will reward you with lower energy costs and longer operating lives. Rather act earlier then later!