  High-energy emission from gamma-ray bursts (GRBs) can give rise to pair
echos, i.e. delayed inverse Compton emission from secondary $e^{\pm}$ pairs
produced in $\gamma-\gamma$ interactions with intergalactic background
radiation. We investigate the detectability of such emission with modern-day
gamma-ray telescopes. The spectra and light curves are calculated for a wide
range of parameters, applying the formalism recently developed by Ichiki et al.
The flux depends strongly on the unknown magnitude and coherence length of
intergalactic magnetic fields, and we delineate the range of field strength and
redshift that allow detectable echos. Relevant uncertainties such as the
high-energy cutoff of the primary gamma-ray spectrum and the intensity of the
cosmic infrared background are addressed. GLAST and MAGIC may be able to detect
pair echo emission from GRBs with redshift $\lesssim 1$ if the primary spectra
extend to $\sim 10 ~ {\rm TeV}$.
