For founders who already have a product, where do you get inspiration for new features and improvements to your app?
The only thing I've always done is look at competitors and decide which of their features is something my userbase would want as well. But that isn't really innovation and feels like we're just playing catch up all the time.
How else can you get inspiration for new and unique features?
The best thing you can do is spend time with your users. How are they using your product in ways you didn't expect? Where are they experiencing friction? What other problems are they having that your app might be able to help with? What kind of "incomplete" stages do they reach in your app, and what kept them from moving forward?
Internal hackathons are another good way to generate new feature ideas if you have employees. Good ideas can come from anyone, and the opportunity to work outside your normal area of responsibility in a low-pressure, experimental event is one of the best ways to get everyone brainstorming.
I'd also recommend looking at ways you can innovate with experience, not functionality. Especially if you're competing in a field with a fairly standard featureset, most of the time it's become so standard because that's the only functionality users want or need. Adding new capabilities is less likely to move the needle than thinking about how to improve the experience of the existing functionality. How can you make what the user does with your app quicker, easier, more enjoyable, or more rewarding?