diff --git a/examples/listen.rb b/examples/listen.rb
index 82ce954..f1d84df 100644
--- a/examples/listen.rb
+++ b/examples/listen.rb
@@ -1,4 +1,7 @@
 require 'ruby-nfc'
+require 'logger'
+
+logger = Logger.new(STDOUT)
 
 puts "Library version: %s" % NFC.version
 readers = NFC::Reader.all
@@ -24,10 +27,10 @@
 			puts "Page 1: %s" % read(1).unpack('H*').pop
 			processed!
 		when IsoDep::Tag
-			select ["F75246544101"].pack('H*')
+			select! ["F75246544101"].pack('H*')
 			# sending APDU command to tag using send_apdu method
 			apdu = ['A00D010018B455CAF0F331AF703EFA2E2D744EC7E22AA64076CD19F6D0'].pack('H*')
-			puts send_apdu(apdu).unpack('H*').pop
+			puts send_apdu(apdu)
 
 			# sending APDU command with "<<" operator which is alias to send_apdu
 			# response = tag << apdu
@@ -35,6 +38,6 @@
 			processed!
 		end
   rescue Exception => e
-    puts e
+    logger.debug e
   end
 end
diff --git a/lib/ruby-nfc/apdu/apdu.rb b/lib/ruby-nfc/apdu/apdu.rb
index 145f51b..f8e1612 100644
--- a/lib/ruby-nfc/apdu/apdu.rb
+++ b/lib/ruby-nfc/apdu/apdu.rb
@@ -86,7 +86,7 @@ def initialize(sw)
 			@code = sw
 			message = STATUS_STRINGS[sw] || "Unknown error"
 
-			super("#{sw.to_s(16)} #{message}")
+			super("#{sw.to_s(16).upcase} #{message}")
 		end
 	end
 end
diff --git a/lib/ruby-nfc/apdu/response.rb b/lib/ruby-nfc/apdu/response.rb
index 5f9aeca..fa3482d 100644
--- a/lib/ruby-nfc/apdu/response.rb
+++ b/lib/ruby-nfc/apdu/response.rb
@@ -38,7 +38,7 @@ def data
 		end
 
 		def to_s
-			@response.unpack('H*').pop
+			@response.unpack('H*').pop.upcase
 		end
 
 		def [](index)
diff --git a/lib/ruby-nfc/tags/isodep.rb b/lib/ruby-nfc/tags/isodep.rb
index cbb3d0c..34defcf 100644
--- a/lib/ruby-nfc/tags/isodep.rb
+++ b/lib/ruby-nfc/tags/isodep.rb
@@ -35,12 +35,6 @@ def connect(&block)
 			)
 
 			if res > 0
-				# trying to select applet if applet identifier was given
-				if aid
-					sw = send_apdu("\x00\xA4\x04\x00#{aid.size.chr}#{aid}")
-					raise IsoDep::Error, "Application not found: #{aid.unpack('H*').pop}" unless "\x90\x00" == sw
-				end
-
 				super(&block)
 			else
 				raise IsoDep::Error, "Can't select tag: #{res}"
@@ -51,6 +45,26 @@ def disconnect
 			0 == LibNFC.nfc_initiator_deselect_target(@reader.ptr)
     end
 
+		# Public: select application with give AID
+		#
+		# aid - Identifier of the application that should be selected
+		#
+		# Returns APDU::Response
+    def select(aid)
+			send_apdu("\x00\xA4\x04\x00#{aid.size.chr}#{aid}")
+    end
+
+		# Public: same as select but raises an APDU::Errno exception if
+		# application not present on the card or SW is not equal to 0x9000
+		#
+		# aid - Identifier of the application that should be selected
+		#
+		# Returns APDU::Response
+		# Raises APDU::Errno
+    def select!(aid)
+    	select(aid).raise_errno!
+    end
+
 		# Public: Select application with given AID (Application Identifier)
 		# 
 		# aid	-	Application Identifier of an applet located on a card
@@ -82,7 +96,7 @@ def send_apdu(apdu)
 
 			raise IsoDep::Error, "APDU sending failed: #{res_len}" if res_len < 0
 
-			APDU::Response.from_string(response_buffer.get_bytes(0, res_len).to_s)
+			APDU::Response.new(response_buffer.get_bytes(0, res_len).to_s)
     end
 
 		# Public: Send APDU command to tag and raises APDU::Errno exception