In the last few years the number of providers for both fixed and mobile calls has increased dramatically, so making sense of all the various “deals” can be an absolute nightmare.
CallCosts.ie, which is run by the Irish Communications Regulator, was setup to help the public make informed decisions without pulling out their hair. Instead of “shopping around” you should be able to see all the various prices in one place by simply “telling” the site what you use your phone for ie. how many minutes etc.,
The site is quite easy to use, though I only wish there were a business version of it!