What is the difference between DPP$-4$ inhibitors and GLP$-1$ analogs?

DPP$-4$ inhibitors increase the level of incretins and GLP$-1$ analogs are incretin mimetics.

GLP$-1$ analogs are mostly pills and DPP$-4$ inhibitors are mostly injections.

GLP$-1$ analogs increase the risk of pneumonitis and DPP$-4$ inhibitors increase the risk of GI upset.

GLP$-1$ analogs act on DPP$-4$ to increase levels of incretins.

GLP$.1$ analogs decrease HbA$1$c by $3\%$ and DPP$-4$ inhibitors decrease Hba$1$c by $1\mathrm{.}5\%.$