This is well intentioned app that does a good job of providing useful features without bloat. There are a couple quirks and some minor annoyances I ran into, but I could use this for personal needs on a daily basis. Client collaboration with this is a no go for me currently.

Pros:
- Calendar views (daily, weekly, monthly)
- File uploads with folder structures
- Messaging (threads / discussions / asynchronous messages)
- Chat
- Start dates for tasks
- Subtasks

Cons:
- There's no real talk of security other than some fluff in their marketing site and privacy policy. Are we encrypted at rest for files and chat? Any plans to pursue third party audits and certifications? Unlimited storage is great, unless there's no security, then it's pointless
- Privacy policy looks like it was copied from another (related?) company. There's at least one mention of another company's name in it, while referring to themselves
- Scheduling tasks for the week calendar was confusing to figure out. The help docs and marketing site show screenshots of the week calendar scheduling, but the daily calendar is the default view when you're using the feature. There should be a feature tour in that view
- Permissions need some work, but I think they're working on that. Although it's nice to see the options for future permission sets in the UI with a coming soon label. I wouldn't say I could use this with clients or even all team members until this feature is more developed
- The date picker for tasks needs a lot of work. It's buggy, especially the quick actions (today, tomorrow) within it. Date ranges are quirky to set up and keyboard shortcuts or an Apply button need to be available. I could only get a due date or a date range set by clicking outside the date picker container, which doesn't feel intuitive at all. It would be nice to be able to set a timezone for specific tasks, along with a default one
- No unlimited subtask hierarchy (nested subtasks). This doesn't matter much to me for my use cases, but it might to other Sumolings so I thought I'd mention it
- No API and doesn't seem like this is a priority for them at this point
- No integrations that I could see, other than Google Drive for embedded docs and files / folders
- Lastly, the UI could use a bit of work. I like the simplicity of this app, but the font choices and overall spacing of elements (board view and calendar especially) leaves a lot to desire for me. The app is super functional, but it's not attractive, especially on ultra-wide screens

Haven't used the mobile apps yet but will install and give them a go.

TLDR; solid, functional app that prioritizes useful features over design and bloat. Can use for personal tasks but not client or team collaboration just yet. The LTD is a good deal for where they're at right now. If they continue developing features and refresh the UI design, this LTD would be a shame to miss out on.

Good luck!