Google App vs Google Tag Manager: Which is more efficient for speeding up my store?

[nastic]

Hello,

I'm trying to speed up my store and use Lighthouse as orientation. In the Lighthouse report I noticed that in the 'Reduce JavaScript Execution Time' I have a "Googe Tag Manager" that costs the site some time. The thing is though, that I never placed Google Tag in the code, I only have the 'Google & Youtube' App installed, where I also have Google Analytics connected, but I can't really use the main purpose of the app because my products can't be sold in Google and Youtube. 

I am now thinking of deleting the app and migrating everything to the Google Tag Manager. Can anybody tell which of the two tools (App and GTM) is better? If I can't sell my products in Google, do I need the app at all if I can have everything in GTM?

Thanks for the help.

[oreoorbitz]

Perfomance wise, it will be the same, since either way you will have google tag manager.

Google tag manager is just that, a tag manager. How many tags are you loading? if you are just loading google analytics, then its best to just load that directly. If you are using analytics, its also worth considering how much tracking information you really need. If you just want to track page visits, and conversions, only load the image pixel tracking, and not the script, that will just track initial page visits, and then on post checkout page you can load the full script and do the conversion tracking and there you can put in more details. 

[SamuelTBeslogic]

Similarly for us, gtag (Google Tag Manager) is the biggest third party offender in terms of blocking execution (taking about half a second) as reported by PageSpeed.
I downloaded the theme to be sure and there's no reference in code.
We have no Custom Pixels.
We only set it up through the "Google & Youtube" Sales Channel.

[oreoorbitz]

Yup, that will cause shopify to load its own setup to send to the dayalayer.