Hey Mr. Green!

I updated my iPhone and find that it now uses far more battery power. Meanwhile, we're about to get rid of our landline because we rarely use it. What's better for our planet in the long run, the smartphone or the landline?

—Catherine in San Anselmo, California

The amount of electricity used by mobile phones is quite low: a kilowatt-hour or two a year if you unplug the charger from the wall after use and a few more kilowatt-hours if you never unplug it. Based on that criterion alone, it's fine to do away with the landline. But with the total revenue from mobile payments worldwide expected to hit $1 trillion next year, there are other big questions to consider when it comes to what's best in the long run for the planet—especially around what will happen to the dozens of different elements in unrecycled phones. Only 10 percent now get recycled, even though, in the case of iPhones, a ton of them could deliver 300 times more gold than a ton of gold ore and 6.5 times more silver than a ton of silver ore. 

Apple has put a new system in place to rapidly disassemble iPhones and sort out their guts. The tech giant can dismantle 2.4 million iPhones a year, though this is less than 1 percent of the 216 million iPhones sold in 2017 alone. That's why some recommend that if your phone is not working properly, you should try to repair it and prolong its life before scrapping it.

My favorite phone system was the 20-by-10-inch oaken box from bygone days, attached to our wall like a hunk of furniture. A phone like that could last forever, while a smartphone's life expectancy is about two and a half years.

Illustration by Little Friends of Printmaking