Stick with low-GI fruits, and limit them to the start of your day.
Blueberries and Strawberries have a low-gi and are full of the rich anti-oxidents you want from fruits.
Oh, BTW....Bell peppers are technically a berry too. Also high in antiox and very low GI. Additionally, green peppers have 2x more vitamin C than an orange, and RED peppers have 3x more vitamin C than an orange and taste much better too.
Apples....some are higher GI than others. Green/GrannySmith are lower GI. Additionally, apples have some chemical in them that makes you feel full....plus there is the benefit of soluable and insoluable fiber.