Investments for your bitcoin can generally be separated into several categories.

(1) High risk, high return short-term trading strategy ("buy low, sell high"): But can you read the market well enough to generate the best trading strategy? For every buyer of a coin, there is a seller, so who is doing it wrong?
(2) Moderate risk, moderate return portfolio investment strategy e.g. Keza (http://www.getkeza.com) as an investment platform.  But you need to invest time in selecting the right investment portfolios based on the composition, underlying beta and future outlook.
(3) Low risk, low return secured lending strategy (collateralised lending).  But need to vet borrowers based on past track record too.

Avoid HYIP, Ponzi schemes, and fanciful, unrealistic promises.

http://themerkle.com/bitcoin-investment-startup-keza-unveils-ios-beta-app/
https://www.producthunt.com/tech/keza
http://getkeza.com/ (It's free to apply for a Keza account)