It looks like Samsung is working on successors of the Galaxy A3 and Galaxy A7. Specifications of the both the phones from the A series have surfaced on GFXBench benchmarking site.
The possible Galaxy A3 successor has a model number SM-A310 as per the listing. It sports a 4.7-inch display with a 720 x 1280 resolution and is powered by 1.5GHz quad-core Exynos 7580 SoC and the Mali-T720 GPU. Running Android 5.1.1, the phone has 1.5GB of RAM and 16GB of native storage. It comes with a 13MP rear and 5MP front camera.
The possible Galaxy A7 on the other hand has a model number SM-A710x. This one sports a 5.5-inch FHD screen with 1080 x 1920 resolution and is powered by 1.5GHz octa-core Snapdragon 615 chipset drives and the Adreno 405 GPU. It comes with 3GB RAM and 16GB of native memory. It also features a 13MP rear and 5MP front facing camera and comes with Android 5.1.1 is pre-installed.
There is no word on when these successors of the Galaxy A3 and Galaxy A7 will be announced. Last week next generation Galaxy A3 and Galaxy A5 were imported to India for testing.