  We discuss the relations between swampland conjectures and observational
constraints on both inflation and dark energy. Using the requirement $|\nabla
V|\geq c V$, with $c$ as a universal constant whose value can be derived from
inflation, there may be no observable distinction between constant and
non-constant models of dark energy. However, the latest modification of the
above conjecture, which utilizes the second derivative of the potential, opens
up the opportunity for observations to determine if the dark energy equation of
state deviates from that of a cosmological constant. We also comment on the
observability of tensor fluctuations despite the conjecture that field
excursions are smaller than the Planck scale.
