Thanks for the demo, I played it on demo but while leave feedback here as Steam comments are not open (as meant for the release).
Settings: it would be nice to get resolution settings, as the only way to toggle fullscreen is to use Alt+Enter apparently (surprisingly, I have better performance in windowed mode with no screen tearing), and even in windowed mode you cannot resize the window. User may also want to be in fullscreen, but at lower resolution to gain performance. But I assume it will be done by the time of Steam release.
UI: it may be more consistent to show an interaction icon whenever an interaction is possible
Dialogues:
When giving a flavor to the ice cream seller, you don’t see a picture of the item given, and the dialogue doesn’t always mention what item was given, it assumes the player knows it. In fact, many items can be given, sometimes it’s not obvious that it could even be used as a flavor, so I didn’t understand some dialogues and forgot what item was in my inventory. Showing the picture and name of the item, and/or referring to them precisely in the dialogue would help. As a bonus, the rewarded colored plastic spoon description could recall what item was given in exchange for this.
When talking to the Bird Lady, she basically offers a 2-day mission due to the low/high tide system. However, I happened to only find her on Day 2, having collected both types of feathers. As a result, the dialogue was a bit odd, where she’d ask me to come back later. Fortunately, I was curious enough to talk to her again, and complete the quest on the spot (she was talking as if one day has passed). Maybe checking the current tide level to adjust dialogue would make it better.
Unfortunately, when it comes to time durations during quests, not specifically the tide system, but in general in adventure games, there is always this weird part where the NPC says “Go and find X!” and the player character is like “Okay, I’ll come back!”. And then if you already had X, you talk again and the player character says “Hey, I found those!” whereas in fact they had it from the beginning. A few games, though, detect if you have X on 1st dialogue and will chain with a special sentence “Oh, I happened to have these”. You may do the same, depending on your writing budget. For the specific case of tides, it may be a little more complicated to write, but should be feasible.
Exploration: when using the hoverboard, looks like the 3 color tokens correspond to 3 layers of music added to the dynamic BGM? Does it also give a boost, or is it just the natural acceleration of the hoverboard that makes you faster? At first, I thought they were collectibles, so I was surprised to see them respawn, but if it’s for boost/music then it makes sense. Sometimes, you lose it a bit fast as you turn a corner, but I think it’s not directly related to turning around a corner, but rather just fading out after a given duration?