Developing an iPhone program on a personal computer contrary to the agreement with the Apple company

He sold land to someone for a deferred payment, and that person sold it for a higher price; can the transaction be cancelled because of the loss?

Ruling on buying and selling Mushafs

Ruling on buying and selling land

Ruling on selling metals which are in the stores of the company that is keeping them

Buying a foreclosed house if it is sold at auction because the borrower is not able to pay off the riba-based loan

Buying zakaah items after giving them to the poor person

Is it permissible to sell Zamzam water?

If his relatives want particular types of perfume, is it permissible for him to buy them and sell them to them?

He wrote in the contract a price higher than that which was paid, and took it from the neighbour