Most businesses provide short quarterly updates, and a more detailed update once a year. You are also welcome to contact the company directly with any questions or suggestions you may have.
If you believe your skill set could add value to the business you have invested in, please reach out to them and suggest having a meeting, or taking on an active role in the company. Businesses at the startup and growth stage are often very busy and may benefit from your contribution, and most entrepreneurs appreciate offers of support from investors. You can also support the business by spreading the good word to friends, family and colleagues about the venture and its crowdfunding raise.
Once a business has completed a round of funding it may need to raise additional funds at a later date in order to continue growing. If you invest in a business that is coming back for second or third round of investment they may contact you to see if you would like to make a further investment.