the result in eclipse are multiple subfolders(armabi armabi-v7) in the folder libs.
That's ok.
The .so file in the armabi folder is (i think) for devices that have no hardware floating point unit - that's generally old or low end devices.
armabi-v7 contains an .so file that is compiled to make use of a hardware floating point unit (ie it's faster than non-floating point unit).
Android will, when you install your app, decide whether to use the .so file from armabi or armabi-v7 based on the device capabilities - it's all handled automatically.
Some libraries even have a
x86 folder with a .so file compiled for Android devices that have x86 CPU, again the Android installation process handles which .so file gets used on the device.
Martin.