Dawn gives you the Dowsing Machine app for Poketch when you're about to enter Mt. Coronet for the first time, after the second Gym, beating Team Galactic in Eterna City, and getting a Bicycle.
you can get it by diging underground or using the item finder thingy. there are also other ways but that's how i get them
your rival gives it to you
Yes.
You can find leftovers where snorlax is. Use the item finder at this spot and you will find the leftovers. You cant use the item finder near it you have to beon top of the spot. It will then say "there is an item under foot" and there it will be.
in rout 228
use the item finder thing near the hotel it should be there.
you can get it by diging underground or using the item finder thingy. there are also other ways but that's how i get them
in a cave
your rival gives it to you
There's no such item/pokemon. Do you mean Giratina?
give the item to a Pokemon and then trade that Pokemon.
get a drowsing macheine (item finder) in the poketech and press any where on the touch screen
nope
Yes.
you dont jack asses from unknown guy
There is no item or Pokemon called an anplogionin in Pokemon Platinum.
The Pokeradar is an item that you get in Pokemon Platinum. You get it from Professor Oak after completing the Shinoh Pokedex.