Preheat the oven to 170. (If your oven doesn't go as low as 170, preheat it to its lowest setting.) Line two baking sheets with silicone liners and set aside.
Add the strawberries, apricots, sugar, and lemon juice to a blender or food processor, and blend until smooth.
Divide the fruit puree between the two baking sheets, and spread evenly.
Bake for 3 hours, rotating the baking sheets after 1 1/2 hours. After 2 1/2 hours, start testing for doneness every 10-15 minutes by lightly tapping the fruit leather with your finger. If it feels slightly tacky but not sticky or wet, it is done.
Let cool, then cut each tray into 8 strips and wrap in parchment paper. Store in an airtight container.