These are some "effective" marketing methods/tactics for your product:
- Getting featured on tech websites e.g. TechCrunch, etc and magazines that your target customers read.
- Kickstarter or Indiegogo campaigns
- Cool youtube video/s highlighting your product in the end.
- Reach out to influencers and ask them to share about the product on social media.
- Participate in a consumer electronics tradeshow. (might be costly)
- Do Google, Facebook, etc ads whenever competing products are being searched.
- Ask your current customers to recommend it to their friends and reward them.
*Effectiveness depends on how you measure it. Different tactics work better at different stages of startup/product cycle. You will have to measure the results to understand which tactics are best for your product.