For now not compatible with Android and not replaceable battery

For now neither the Polar Beat application or Runtastic are compatible with this product.
Runtastic, but recognizes it gives neither pace nor speed for now in the Android release.
Not until the update. Apparently the iPhone, it already works for Runtastic.
Otherwise, the battery of these sensors is not interchangeable. It's a pity in my opinion; because it will buy a new
set of sensors when the batteries are empty.