I have been using Google Firebase since 2018.

I have been using Google Firebase for four years.

I have been using the solution for one to two years.

I have been using the solution for more than five years.

I have been using Google Firebase for three years.

I've been using the solution for two years.

I have used Google Firebase for a short period of time while working on a few projects.

I've been using the solution for five years. 

I have been using Google Firebase for a couple of months. I use the solution's latest version.

I have been using the solution for three years and two months.

I have been using Google Firebase for four to five years. I am just a customer of the solution.

I have been using Google Firebase for approximately five years.

I've been using Google Firebase for almost one year now.

We have been using Google Firebase for a few years.

I have been using Google Firebase for the past two years.

I have been using Google Firebase for approximately one and a half years.

I have been using Google Firebase for two years.

I've been using it for about six or seven months.

I have been using Google Firebase for about 18 months.

I've been using Firebase for two years at my current company, but they were using it before I was hired. 

I have been using the solution for the last four years.

I have used this solution for three years. 

I've been using the solution for the last two years.

I've been using the solution for two months.

I have been using Google Firebase for approximately four years.