Displaying and updating a counter in bash

for i in {0..15}; do echo -ne "$i"'\r'; sleep 1; done; echo 

You don't need ..1 for stepwidth 1 which is default.

echo -n 

prevents newlines.

\r is returning to begin of line (without newline - \n), and better than my formerly used '\b' for backstepping a single character, unhandy, if you have more than one digit-numbers. Thanks to rozcietrzewiacz.