Two novel applications of chaotic dynamics for the construction of simple highly accurate measuring
devices and for secure image ciphering are presented. We suggest to utilize the sensitivity to initial
conditions as a mechanism for accurate measurements. We describe an algorithm which takes low accuracy
time evolution data of a chaotic circuit to reconstruct the initial condition (signal to be measured)
with a much higher accuracy.
In the second part of the paper, the baker map and the cat map are
used to create a complex permutation of pixels in a digital image. The ciphering / deciphering process,
and the security of the cipher are discussed.