I've figured that exiting an APP by simply using "ret" causes ram resets, so after some searching I fount that the prober way to exit an APP is by using the instruction :
bjump _JforceCmdNoChaR
However, when I try to compile it, my assembler (AppDev) gives the following error message:

"Macro expects args but none found"

What's the deal with this? Am I using the wrong command? or what arguments am I supposed to use?
If any more information is needed, just ask.
Hope someone can help me out here!

Actually, if you want to take the lazy way out which may or may not be easier in this case, just copy your data to ram first and then you can use your handy dandy bcalls with the ram location.  If you have enough room, you can just copy all that data there at the beginning and then you're all set.  If not, then you can dynamically copy the text/sprites to the ram only when you need them.

Smart :O
But I think copying the whole deal at the start would'nt work, since I turned it into an APP because of the 8kB limit, and the programm might get much larger even.
I guess the 8kB limit is still an issue when you just copy the lot at the start, so you're second solution sounds nice to me.

This might be asking for a bit too much, but can you provide me with an example scrip that, lets say, displays the "Hello World!" message in small font on a specific location?
That way things will get more concrete to me, or maybe you can tell me how to "dynamically copy the text/sprites to the ram only when you need them". (with a small script please!)

I'm sorry if I'm being very demanding here, after all I'm pretty much asking fr33 st00f here on a forum...
Thanks alot!

Thanks for your reply!

But have you equated xpos, ypos and clip_mask to a location on safe ram?

Probably not...
How do I do this?
I'm actually quite a newby with ASM, so don't be afraid to explain "too much".

If you want to ease some coding it is easier to use:
appsafePutS:
   ld a,(hl)
   inc hl
   or a
   ret z
   b_call _PutC
   jr appPutS

 ld hl,string
 call appsafePutS

than relocating the string to ram every time.

Uhm...
Can you use this in an easy example for me please?
Like, lets say I want the "Hello World!" message displayed at a specific location.
How would I do that youre way?

Thanks for the help!
It's REALLY appreciated.

    LD    BC, ______     ; _____ is the length of your string in characters, INCLUDING the zero at the end

I'll try, but you mean I load the number in BC that contains the number of characters +1?
So "Hello World!" would be
     LD     BC, 13
?

I'll try and see, as for the sprites it might be a self-modifieing code, like Quigibo said.
Unfortunately I can't touch the PC with the programming tools right now, but I'll try all suggestions later.
Thanks.

Replaced all the "b_call_PutS" with "call app_PutS" and included the small routine, but it's still messed up.
It does show the text now, though its in large font, and no where near where I want it.
Also, I can't applie it to sprites
I'm probably doing something wrong, but what's the normal way to display sprites/small text in an app where I want when I want?
Works when I use TASM to assemble and run it, but in an app its all still random junk on the screen, QQ.

Well, your app page is mapped in at addresses $4000-$7fff. When you do a Bcall, the OS page with the routine is temporarily put there, so the data pointed to by HL will no longer be your text. That's why it works if you read your text data and display each character manually, since the OS will not be trying to read data from your APP.

I start to get it...
Though I still don't understand how your posted code can help.
What do I do in order to show sprited/text the right way?
I don't know what to do with the code you gave me, sorry :C

I've finally created an App, but when I run it, all sprites/text in the screen is messed up.
Everything does work, it reacts correctly to buttons pressed, but whenever I use a sprite or do something like :
    LD     HL, $0006
    LD     (CurRow), HL
    LD    HL, Sometext
    b_call _PutS
the screen fills with random stuff.
The program doesn't crash, I can still switch between menus by pressing the correct buttons (I made the priogram, so I can navigate blind in it), but like said, text shown as above and sprites dont work.

The programm worked fine before being turned into an App, and most sprites seem to show in the upper left corner of the screen, instead of twhere they're supposed to be.

I've used AppDev to compile the .z80 into an app.
Has anyone encountered the same problem?
How to fix this?
As said befire, when I normally compile it, it works perfectly fine.
I'm exeeding the 8kB limit though, so that's why I'm turining it into an App.
If I need to include more info, just ask and I'll post it.

Some random info that might/might not be related to the problem:
My header:
#INCLUDE "DWEDIT.INC"
#IFDEF APP
.org $4000

#IFNDEF NOAPPHEADER
;This is the application header definition area required for all apps.
 .db 080h,0Fh    ;Field: Program length
 .db   00h,00h,00h,00h ;Length=0 (N/A for unsigned apps)
 .db 080h,012h    ;Field: Program type
 #ifdef TI73
  .db 01h, 02h  ;type=Shareware, TI-73
 #else
  .db   01h,04h  ;Type= Shareware, TI-83Plus
 #endif
 .db 080h,021h    ;Field: App ID
 .db   01h       ;Id = 1
 .db 080h,031h    ;Field: App Build
 .db   01h       ;Build = 1
 .db 080h,048h    ;Field: App Name
 .db "CalcHero"
 .db 080h,081h    ;Field: App Pages
 .db 1
 .db 080h,090h    ;No default splash screen
 .db 03h,026h ,09h,04h, 04h,06fh,01bh,80h     ;Field: Date stamp- 5/12/1999
 .db 02h,0dh,040h                             ;Dummy encrypted TI date stamp signature
 .db 0a1h ,06bh ,099h ,0f6h ,059h ,0bch ,067h
 .db 0f5h ,085h ,09ch ,09h ,06ch ,0fh ,0b4h ,03h ,09bh ,0c9h
 .db 03h ,032h ,02ch ,0e0h ,03h ,020h ,0e3h ,02ch ,0f4h ,02dh
 .db 073h ,0b4h ,027h ,0c4h ,0a0h ,072h ,054h ,0b9h ,0eah ,07ch
 .db 03bh ,0aah ,016h ,0f6h ,077h ,083h ,07ah ,0eeh ,01ah ,0d4h
 .db 042h ,04ch ,06bh ,08bh ,013h ,01fh ,0bbh ,093h ,08bh ,0fch
 .db 019h ,01ch ,03ch ,0ech ,04dh ,0e5h ,075h
 .db 80h,7Fh      ;Field: Program Image length
 .db   0,0,0,0    ;Length=0, N/A
 .db   0,0,0,0    ;Reserved
 .db   0,0,0,0    ;Reserved
 .db   0,0,0,0    ;Reserved
 .db   0,0,0,0    ;Reserved
#ENDIF
#ENDIF

Oh, and I use this to put a sprite on the screen:
    LD A, 46 ; Random number
    LD (ypos), A
    LD A, 27 ; another Random number
    LD (xpos), A
    LD B, 18 ; Length of sprite in Y direction
    LD      DE, (ypos)
    LD      IX, Sprite ; Label of the sprite
    CALL Showsprite

Showsprite: ; Show Sprite (XOR)
        CALL    ClipSprXOR
        b_call _GrBufCpy
ret
ClipSprXOR: ; Show Sprite XOR
    LD     A, %11111111
    LD     (clip_mask), A
    LD     A, E
    OR     A
    JP     M, ClipTop
    SUB    64
    RET    NC
    NEG
    CP     B
    JR     NC, VertClipDone
    LD     B, A
    JR     VertClipDone
ClipTop:
    LD     A, B
    NEG
    SUB    E
    RET    NC
    PUSH   AF
    ADD    A, B
    LD     E, 0
    LD     B, E
    LD     C, A
    ADD    IX, BC
    POP    AF
    NEG
    LD     B, A
VertClipDone:
    LD     C, 0
    LD     A, D
    CP     -7
    JR     NC, ClipLeft
    CP     96
    RET    NC
    CP     89
    JR     C, HorizClipDone
ClipRight:
    AND    7
    LD     C, A
    LD     A, %11111111
FindRightMask:
    ADD    A, A
    DEC    C
    JR     NZ, FindRightMask
    LD     (clip_mask), A
    LD     A, D
    JR     HorizClipDone
ClipLeft:
    AND    7
    LD     C, A
    LD     A, %11111111
FindLeftMask:
    ADD    A, A
    DEC    C
    JR     NZ, FindLeftMask
    CPL
    LD     (clip_mask), A
    LD     A, D
    ADD    A, 96
    LD     C, 12
HorizClipDone:
    LD     H, 0
    LD     D, H
    LD     L, E
    ADD    HL, HL
    ADD    HL, DE
    ADD    HL, HL
    ADD    HL, HL
    LD     E, A
    SRL    E
    SRL    E
    SRL    E
    ADD    HL, DE
    LD     DE, PlotSScreen
    ADD    HL, DE
    LD     D, 0
    LD     E, C
    SBC    HL, DE
    AND    7
    JR     Z, _Aligned
    LD     C, A
    LD     DE, 11
_RowLoop:
    PUSH   BC
    LD     B, C
    LD     A, (clip_mask)
    AND    (IX)
    LD     C, 0
_ShiftLoop:
    SRL    A
    RR     C
    DJNZ   _ShiftLoop
    XOR    (HL)
    LD     (HL), A
    INC    HL
    LD     A, C
    XOR    (HL)
    LD     (HL), A
    ADD    HL, DE
    INC    IX
    POP    BC
    DJNZ   _RowLoop
    RET
_Aligned:
    LD     DE, 12
_PutLoop:
    LD     A, (IX)
    XOR    (HL)
    LD     (HL), A
    INC    IX
    ADD    HL, DE
    DJNZ   _PutLoop
    RET


You're my new God, Quigibo...
Though when I click you're file, I get the following:

---copying file *myProgName*.z80----
Unable to find the given Pad       (<-- not exactly what it says, sorry, my error is in Dutch, and I can't translate it well)
---assembling *MyProgName*.z80----
Unable to find the given Pad         (same error as above)

Could be something with the header, what exactly do you mean with *You also need a special header for the app.*
How should the header look like?