Kayako

Easy to use, depending on your license is very customizable.
Once the ticket is created adding notes, screenshots and files is really simple and fast

API or link to CRM directly is really needed
External add on works but with serious limitations.
Old kayako had a voip system to do phone calls

I have used kayako as a knowledge base for my software. I have integrated pages into my software and spent development dollars in doing so, and written hundreds of articles for the knowledge base. A few days ago I received an email from kayako requesting that I contact them about my renewal. When I did, they informed me they would be increasing their pricing by 600% for this year, and an additional 25% each year thereafter. I was shocked, and asked for clarification, explaining that I am a small company that is in the events industry - I have been shut down due to events being shut down because of the pandemic. Even in normal circumstances, I wouldn't be able to afford that ridiculous price increase. They informed me they would be cancelling my service. I have spent hundreds of hours creating these knowledge base articles, thinking I would be using these for years to come - now I have to spend development dollars to integrate a new knowledge base into my software, and re-do all of the articles on a new platform. Very dishonest business practices - untrustworthy services - and costing the client time and money.

Raising prices by 600% out of nowhere, causing my small business to have to move to another platform, after spending time and money.

It it nice to be able to pull up multiple conversations/tickets within one window, as it made it easy to switch between current ongoing projects and also complete research with little confusion. Also, Kayako shows in real-time who is looking at a ticket, thus it made it easy for Customer Service as we could see if someone was already working on that ticket. One of the nice things about Kayako was the ability to see when the recipients of an email opened it or looked at it. If there were several recipients, it would break down who opened the email, when. Thus, from a documentation standpoint, if someone was claiming to have never received an email, we were able to show that they had in fact opened the email.

There were few reporting tools and there was no way to set follow-up tasks. We relied on setting reminders on another system like our Google calendar. Also, Kayako was getting quite expensive, which was one of the big factors in our company switching to a different ticketing system.

Admin tools for automatically dealing with tickets are great. Actually handling tickets is very easy, as is adding internal notes.

Agent ability to search tickets is lacking. We had to make some changes to let our supervisors see every ticket message even if it is deleted by an agent.
We could never get the knowledgebase to work the way we wanted.
Sometimes it is not clear who is getting copied on any specific ticket reply.