Consider the market for mobile applications, smartphones, and conventional phones. For each pair, identify whether they are complements or substitutes: Pairs of Goods and Services Complements Substitutes
Mobile applications and smartphones
Mobile applications and conventional phones
Smartphones and conventional phones

Mobile Applications and Smart Phones are Complements

Smart Phones and Conventional Phones are Substitutes

Mobile Applications and Conventional Phones are substitutes.

Explanation:

Complement goods are goods that can be used or consumed together. E.g. car and gas. A car would not work without gas. A rise in price of a good leads to a fall in demand of the complement good.

Subsituite goods rival one another in consumption. They can be used in place of another good.

A rise in price of a good leads to a rise in demand of the other good.

I hope my answer helps you

you don't if you paid you paid. it's like if i bought a computer and used it then i say idon't want it anymore so im gonna return it. you can't. unlkess you have your reciept