Eu adicioneipaypal no meu aplicativo, anteriormente estava funcionando bem, mas percebi que o tamanho do meu apk ficou maior, então encontrei uma solução para isso

eu adicionei isso ao meugradle

 compile('com.paypal.sdk:paypal-android-sdk:2.12.3') {
        exclude group: 'io.card'
    }

com o uso disso, o tamanho do meu apk não aumentou, mas então eu executo meu aplicativo, ele falha

 Process: com.android.msahakyan.expandablenavigationdrawer, PID: 16317
    java.lang.RuntimeException: An error occurred while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java:309)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
            at java.lang.Thread.run(Thread.java:818)
     Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Lio/card/payment/CardIOActivity;
            at com.paypal.android.sdk.payments.ds.doInBackground(Unknown Source)
            at android.os.AsyncTask$2.call(AsyncTask.java:295)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
            at java.lang.Thread.run(Thread.java:818)
     Caused by: java.lang.ClassNotFoundException: Didn't find class "io.card.payment.CardIOActivity" on path: DexPathList[[zip file "/data/app/com.android.msahakyan.expandablenavigationdrawer-1/base.apk"],nativeLibraryDirectories=[/data/app/com.android.msahakyan.expandablenavigationdrawer-1/lib/x86, /vendor/lib, /system/lib]]
            at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
            at com.paypal.android.sdk.payments.ds.doInBackground(Unknown Source)
            at android.os.AsyncTask$2.call(AsyncTask.java:295)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
            at java.lang.Thread.run(Thread.java:818)
    Suppressed: java.lang.ClassNotFoundException: io.card.payment.CardIOActivity
            at java.lang.Class.classForName(Native Method)
            at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
            at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
            ... 8 more
     Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available