All you need is:
Salt (34p for a bag from Sainsbury's)
Take a small handful of fruit and mash it up either by hand or food processor. Add a tiny bit of water if using a processor. In a bowl mix in the salt until you have a thick salt consistency. Add to jars and label. The salt preserves the fruit and it doesn't need to be kept in the fridge. I have some that has lasted months. It smells delicious!