delphi multi device form, where do i save a text file

Question

I am making a simple multi device application for my android phone to help me log my hours at work. I have never programmed a MDA before and still a novice in programming. I cant seam to find out where to save the text file since regardless of how I refer to the file location, it cant find it.

I have also tried hardcoding the file creation prior to checking its existence.

here's my initial attempt at this problem.

// writes the days log to log.txt
procedure TForm1.btnlogClick(Sender: TObject);
var
  tlog: textfile;
  ihours: integer;
  sact, sdate, slog: string;

begin
  // gets data from user
  ihours := strtoint(sbhours.text);

  if rbCoach.ischecked then
  begin
    sact := 'Coaching';
  end
  else
    sact := 'Umpiring';

  sdate := datetostr(Calendar.date);

  // assigns teh file and writes to it
  if fileexists('logs.txt') = false then
  begin
    showmessage('Log File Does Not Exist!');
    filecreate('logs.txt');
    exit;
  end;

  assignfile(tlog, 'logs.txt');
  reset(tlog);

  slog := sdate + '#' + sact + '#' + inttostr(ihours);
  writeln(tlog, slog);
  closefile(tlog);
end;














// on startup it outputs current log to the memo
procedure TForm1.FormActivate(Sender: TObject);
var
  tlog: textfile;
  slog: string;
  ihash: integer;

  ihours: integer;
  sact, sdate: string;
begin
  // assigns file

  if fileexists('logs.txt') = false then
  begin
    showmessage('Log File Does Not Exist!');
    filecreate('logs.txt');
    exit;
  end;

  assignfile(tlog, 'logs.txt');
  reset(tlog);

  // adds logs to memo
  Memlog.lines.add('Date:        Activity:        Hours:   ');
  while NOT EOF(tlog) do
  begin
    readln(tlog, slog);
    ihash := pos('#', slog);
    sdate := copy(slog, 1, ihash);
    delete(slog, 1, ihash);

    ihash := pos('#', slog);
    sact := copy(slog, 1, ihash);
    delete(slog, 1, ihash);

    ihash := pos('#', slog);
    ihours := strtoint(copy(slog, 1, ihash));
    delete(slog, 1, ihash);
    //              ('Date:        Activity:         Hours:   ');
    Memlog.lines.add(sdate + '   ' + sact + '    ' + inttostr(ihours));

  end;
  closefile(tlog);
end;