FENTEC project provided the first fully-fledged functional encryption library. By fully-fledged we mean a library where the user can choose via an easy-to-use API between different schemes and each scheme can be instantiated from different cryptographic primitives.
FENTEC library actually comes in two flavors: GoFE is written in Go, while CiFEr is written in C.
Currently there is a growing concern for privacy. Media constantly warns of the dangers of publicly exposing details of our lives. For instance, some details leak when we make digital payments and this information remains in the net. When we buy with a bank card, make payments with mobile phones or with other digital means of payment such as Paypal, a great amount of data is exchanged. This information is not only of personal nature, but it also reveals our habits and customs.