Are there any other way without spending money on Google Ads?
building an audience but that takes a lot of time(so kind of like loosing money)
coldmailing if it's B2B?(with stuff like lemlist, there is a free version)
Controversial but still working: social media bots
even more controversial: google ads won't charge you until you reach about 300$ of spending, so if you have a prepaid or lockable debit card you can test stuff pretty much for free. if you actually earn more that you would have spent then you can start actually paying
sshhh ;)
1. Have a Twitter account and follow folks who would be interested. Some follow back. 2. Write blog posts about it. Spend some time to make it high quality to increase the chance that search engines rank it higher. Also, high quality improves reputation and confidence. 3. Tweet every time you blog or release. 4. Tweet about subjects of interest related to your software. 5. Engage in the community around the subject of your software. 6. Contribute to the community - #GiveFirst (maybe this should be first).
While I mention Twitter (I feel like it's one of the best channels), there are other social media channels to look at - whatever makes sense for your situation. There are meetups, YouTube, and other ways that you can generate content that people might care about. Also, my situation is open source and not a product for sale, YMMV.