tenses - Difference between "I reached home" and "I have reached home"

I often confuse these two things:
"I reached home" and "I have reached home".
Once my friend asked me, "Where are you? "
I messaged him: "I have reached home".
He told me not to use "have reached "...

reached = past tense, have reached = present perfect

Can someone please clear this doubt so that I don't make the mistake again.

Answer

If you were texting the message as you were getting home, or just after arriving home than it should be:
"I've reached home."
You use the present perfect because the time of the action is not specified and the important information is that your journey's over and you are now at home.

If you specified a time then you'd have had to use the preterite:
"I reached home a couple of minutes ago (at 10...)."
Or if you were in a sequence of events, e.g :
"I reached home and had somethingto eat."