Requesting geolocation through SMS from Arduino controlled GSM and GPS modules.

Projects Programming
2 
 if(cell.available() > 0)
{
inchar = cell.read();
 if (inchar == '#') // the start of our command
{
delay(10);
inchar = cell.read();
 if (inchar == 'a')
{
delay(10);
inchar = cell.read();
if (inchar == '0')
 {
   SendMsg();

Perhaps you aren't delaying long enough hoping for the next character to arrive. Either learn to use end of packet markers or use

delay(10000000000000);

That should certainly be long enough.