diff --git a/protob/messages.proto b/protob/messages.proto
index 5b89e836aa..94255cfb6f 100644
--- a/protob/messages.proto
+++ b/protob/messages.proto
@@ -77,24 +77,24 @@ message Initialize {
 
 // Response object for Initialize.
 message Features {
-	optional bytes vendor = 1;				// Name of the manufacturer, e.g. "bitcointrezor.com"
+	optional string vendor = 1;				// Name of the manufacturer, e.g. "bitcointrezor.com"
 	optional uint32 major_version = 2;			// Major version of the device, e.g. 1
 	optional uint32 minor_version = 3;			// Minor version of the device, e.g. 0
 	optional uint32 bugfix_version = 4;
 	optional bool bootloader_mode = 5;
-	optional bytes device_id = 6 [(binary) = true];		// Device's unique identifier
+	optional string device_id = 6;				// Device's unique identifier
 	optional bool pin_protection = 7;			// True if Trezor is covered by PIN
 	optional bool passphrase_protection = 8;		// True if node/mnemonic is covered by passphrase
-	optional bytes language = 9;
-	optional bytes label = 10 [(binary) = true];
+	optional string language = 9;
+	optional string label = 10;
 	repeated CoinType coins = 11;
 	optional bool initialized = 12;			// True if device cointains seed
 }
 
 // Overwrites only filled fields of the structure
 message ApplySettings {
-	optional bytes language = 1;
-	optional bytes label = 2 [(binary) = true];
+	optional string language = 1;
+	optional string label = 2;
 }
 
 // Starts workflow for setting/changing the PIN
@@ -107,7 +107,7 @@ message ChangePin {
 //
 // Response: None or Success
 message Ping {
-	optional bytes message = 1;	// Message will be sent back in Success message
+	optional string message = 1;	// Message will be sent back in Success message
 	optional bool button_protection = 2; // Ask for button press
 	optional bool pin_protection = 3;	// Ask for PIN if set
 	optional bool passphrase_protection = 4;	// Ask for passphrase if set
@@ -115,13 +115,13 @@ message Ping {
 
 // Response object defining success of the previous request
 message Success {
-	optional bytes message = 1;	// May contain human readable description of the action or request-specific payload
+	optional string message = 1;	// May contain human readable description of the action or request-specific payload
 }
 
 // Response object defining failure of the previous request
 message Failure {
 	optional FailureType code = 1;		// May contain computer-readable definition of the error state
-	optional bytes message = 2;		// May contain human-readable message of the error state
+	optional string message = 2;		// May contain human-readable message of the error state
 }
 
 // Message can be sent by the *device* as a resopnse to any request.
@@ -130,7 +130,7 @@ message Failure {
 // the original request.
 message ButtonRequest {
 	optional ButtonRequestType code = 1;
-	optional bytes data = 2 [(binary) = true];
+	optional string data = 2;
 }
 
 // Computer agrees to wait for HW button press.
@@ -142,12 +142,12 @@ message ButtonAck {
 //
 // Response: PinMatrixAck, Cancel
 message PinMatrixRequest {
-	optional bytes message = 1;	// Human readable message
+	optional string message = 1;	// Human readable message
 }
 
 // Message is sent by the computer as a response to PinMatrixRequest previously sent by the device.
 message PinMatrixAck {
-	required bytes pin = 1;		// User must write down the password for accessing the device.
+	required string pin = 1;		// User must write down the password for accessing the device.
 }
 
 // Message is sent as a cancel response to ButtonRequest, PinMatrixRequest and PassphraseRequest
@@ -160,7 +160,7 @@ message PassphraseRequest {
 
 // Computer sends passphrase to device.
 message PassphraseAck {
-	required bytes passphrase = 1 [(binary) = true];
+	required string passphrase = 1;
 }
 
 // Request a sample of random data generated by hardware RNG. May be used
@@ -173,7 +173,7 @@ message GetEntropy {
 
 // Response to GetEntropy request contains random data generated by internal HRNG.
 message Entropy {
-	required bytes entropy = 1 [(binary) = true];	// Stream of generated bytes
+	required bytes entropy = 1;	// Stream of generated bytes
 }
 
 // Ask device for public key corresponding of address_n path. This may be used for generating
@@ -191,11 +191,11 @@ message PublicKey {
 
 message GetAddress {
 	repeated uint32 address_n = 1;	// Parameter for address generation algorithm to derive the address from the master node
-	optional bytes coin_name = 2 [default='Bitcoin'];
+	optional string coin_name = 2 [default='Bitcoin'];
 }
 
 message Address {
-	required bytes address = 1;	// Bitcoin address in base58 encoding corresponding to GetAddress(n) call
+	required string address = 1;	// Bitcoin address in base58 encoding corresponding to GetAddress(n) call
 }
 
 // Request device to wipe all sensitive data and settings.
@@ -209,12 +209,12 @@ message WipeDevice {
 //
 // Response: Success, ButtonRequest, PinMatrixRequest, Failure
 message LoadDevice {
-	optional bytes mnemonic = 1;	// Seed encoded as a mnemonic (12 english words)
+	optional string mnemonic = 1;	// Seed encoded as a mnemonic (12 english words)
 	optional HDNodeType node = 2;
-	optional bytes pin = 3;		// Set PIN protection for important actions
+	optional string pin = 3;		// Set PIN protection for important actions
 	optional bool passphrase_protection = 4;
-	optional bytes language = 5 [default='english'];
-	optional bytes label = 6 [(binary) = true];
+	optional string language = 5 [default='english'];
+	optional string label = 6;
 	optional bool skip_checksum = 7; // Do not test mnemonic for valid BIP39 checksum
 }
 
@@ -233,8 +233,8 @@ message ResetDevice {
 	optional uint32 strength = 2 [default=128]; // Strength of seed in bits
 	optional bool passphrase_protection = 3;
 	optional bool pin_protection = 4;
-	optional bytes language = 5 [default='english'];
-	optional bytes label = 6 [(binary) = true];						
+	optional string language = 5 [default='english'];
+	optional string label = 6;
 }
 
 // Asks for additional Entropy from host computer
@@ -243,7 +243,7 @@ message EntropyRequest {
 
 // Provide additional entropy for seed generation function.
 message EntropyAck {
-	optional bytes entropy = 1 [(binary) = true];	// Recommended to provide 256 bits (32 bytes) of random data.
+	optional bytes entropy = 1;	// Recommended to provide 256 bits (32 bytes) of random data.
 }
 
 // Starts workflow of asking user for specific words of his mnemonic.
@@ -253,9 +253,9 @@ message RecoveryDevice {
 	optional uint32 word_count = 1;	// How many words is in mnemonic sentence?
 	optional bool passphrase_protection = 2;
 	optional bool pin_protection = 3;
-	optional bytes language = 4 [default='english'];
-	optional bytes label = 5 [(binary) = true];
-	optional bool enforce_wordlist = 6;	// Trezor enforces BIP39 wordlist						
+	optional string language = 4 [default='english'];
+	optional string label = 5;
+	optional bool enforce_wordlist = 6;	// Trezor enforces BIP39 wordlist
 }
 
 // This message indicates that device is asking user for some word of his mnemonic.
@@ -264,7 +264,7 @@ message WordRequest {
 }
 
 message WordAck {
-	required bytes word = 1 [(binary)=true];	// One word of mnemonic on asked position
+	required string word = 1;	// One word of mnemonic on asked position
 }
 
 // ****************************************************************************
@@ -274,19 +274,19 @@ message WordAck {
 
 message SignMessage {
 	repeated uint32 address_n = 1;
-	required bytes message = 2 [(binary) = true];
-	optional bytes coin_name = 3 [default='Bitcoin'];
+	required bytes message = 2;
+	optional string coin_name = 3 [default='Bitcoin'];
 }
 
 message VerifyMessage {
-	optional bytes address = 1;
-	optional bytes signature = 2 [(binary) = true];
-	optional bytes message = 3 [(binary) = true];
+	optional string address = 1;
+	optional bytes signature = 2;
+	optional bytes message = 3;
 }
 
 message MessageSignature {
-	optional bytes address = 1;
-	optional bytes signature = 2 [(binary) = true];
+	optional string address = 1;
+	optional bytes signature = 2;
 }
 
 // Estimate size of the transaction
@@ -300,7 +300,7 @@ message MessageSignature {
 message EstimateTxSize {
 	required uint32 outputs_count = 1;		// Count of outputs of the transaction
 	required uint32 inputs_count = 2;		// Count of inputs of the transaction
-	optional bytes coin_name = 3 [default='Bitcoin'];
+	optional string coin_name = 3 [default='Bitcoin'];
 }
 
 // Result of EstimateTxSize
@@ -314,7 +314,7 @@ message TxSize {
 message SignTx {
 	required uint32 outputs_count = 1;		// Count of outputs of the transaction
 	required uint32 inputs_count = 2;		// Count of inputs of the transaction
-	optional bytes coin_name = 3 [default='Bitcoin'];
+	optional string coin_name = 3 [default='Bitcoin'];
 }
 
 // Request a simplified workflow of signing.
@@ -333,7 +333,7 @@ message SimpleSignTx {
 	repeated TxInputType inputs = 1;
 	repeated TxOutputType outputs = 2;
 	repeated TransactionType transactions = 3;
-	optional bytes coin_name = 4 [default='Bitcoin'];
+	optional string coin_name = 4 [default='Bitcoin'];
 }
 
 // Sent by the device as a response for SignTx. Device asks for information for signing transaction.
@@ -344,8 +344,8 @@ message TxRequest {
 	optional int32 request_index = 1;			// If >=0, device expects TxInput/TxOutput message from the computer
 	optional RequestType request_type = 2;		// Ask for TxInput or TxOutput?
 	optional int32 signed_index = 3;			// If >=0, 'signature' contains signed input of this input
-	optional bytes signature = 4 [(binary) = true];		// If signed_index>=0, represent signature of the signed_index input
-	optional bytes serialized_tx = 5 [(binary) = true];	// Part of serialized and signed transaction
+	optional bytes signature = 4;		// If signed_index>=0, represent signature of the signed_index input
+	optional bytes serialized_tx = 5;	// Part of serialized and signed transaction
 }
 
 // Transaction onput for SignTx workflow. It is response to TxRequest message sent by device.
@@ -370,7 +370,7 @@ message FirmwareErase {
 }
 
 message FirmwareUpload {
-	required bytes payload = 1 [(binary) = true];		// Firmware to flash into device
+	required bytes payload = 1;		// Firmware to flash into device
 }
 
 // ****************************************************************************
@@ -394,13 +394,13 @@ message DebugLinkGetState {
 
 // Response object reflecting device's current state. It can be received only over debug link connection.
 message DebugLinkState {
-	optional bytes layout = 1 [(binary) = true];		// Raw buffer of display
-	optional bytes pin = 2;					// Current PIN, blank if PIN is not set/enabled
-	optional bytes matrix = 3;				// Current PIN matrix
-	optional bytes mnemonic = 4;				// current mnemonic format
+	optional bytes layout = 1;				// Raw buffer of display
+	optional string pin = 2;					// Current PIN, blank if PIN is not set/enabled
+	optional string matrix = 3;				// Current PIN matrix
+	optional string mnemonic = 4;				// current mnemonic format
 	optional HDNodeType node = 5;				// current node (BIP32 format)
 	optional bool passphrase_protection = 6;
-	optional bytes word = 7;		// What word is on display in RecoveryDevice/ResetDevice workflow
+	optional string word = 7;		// What word is on display in RecoveryDevice/ResetDevice workflow
 	optional int32 word_pos = 8;	// Which word of mnemonic do the device expect
 	optional bytes entropy = 9;		// Return current entropy of ResetDevice workflow
 }
@@ -411,6 +411,6 @@ message DebugLinkStop {
 
 message DebugLinkLog {
 	optional uint32 level = 1;
-	optional bytes bucket = 2;
-	optional bytes text = 3;
+	optional string bucket = 2;
+	optional string text = 3;
 }
diff --git a/protob/storage.proto b/protob/storage.proto
index 9ec7359d1c..7de4a34268 100644
--- a/protob/storage.proto
+++ b/protob/storage.proto
@@ -15,10 +15,10 @@ import "types.proto";
 message Storage {
 	required uint32 version = 1;
 	optional HDNodeType node = 2;
-	optional bytes mnemonic = 3 [(binary) = true];
+	optional string mnemonic = 3;
 	optional bool passphrase_protection = 4;	// whether node_serialized or mnemonic are encrypted (protected by passphrase)
 	optional uint32 pin_failed_attempts = 5;
-	optional bytes pin = 6;
-	optional bytes language = 7;
-	optional bytes label = 8 [(binary) = true];
-}
\ No newline at end of file
+	optional string pin = 6;
+	optional string language = 7;
+	optional string label = 8;
+}
diff --git a/protob/types.proto b/protob/types.proto
index 95150b0ce4..51ca608824 100644
--- a/protob/types.proto
+++ b/protob/types.proto
@@ -12,10 +12,6 @@ option java_outer_classname = "TrezorType";
 
 import "google/protobuf/descriptor.proto";
 
-extend google.protobuf.FieldOptions {
-	optional bool binary = 50001;	// message field has binary payload
-}
-
 extend google.protobuf.EnumValueOptions {
 	optional bool wire_in = 50002;	// message can be transmitted via wire from PC to TREZOR
 	optional bool wire_out = 50003;	// message can be transmitted via wire from TREZOR to PC
@@ -66,32 +62,32 @@ message HDNodeType {
 	required uint32 depth = 1;
 	required uint32 fingerprint = 2;
 	required uint32 child_num = 3;
-	required bytes chain_code = 4 [(binary) = true];
-	optional bytes private_key = 5 [(binary) = true];
-	optional bytes public_key = 6 [(binary) = true];
+	required bytes chain_code = 4;
+	optional bytes private_key = 5;
+	optional bytes public_key = 6;
 }
 
 message CoinType {
-	optional bytes coin_name = 1;
-	optional bytes coin_shortcut = 2;
+	optional string coin_name = 1;
+	optional string coin_shortcut = 2;
 	optional uint32 address_type = 3;
 	optional uint64 maxfee_kb = 4;
 }
 
 message TxInputType {
 	repeated uint32 address_n = 1;			// Parameter for address generation algorithm to derive the address from the master node
-	required bytes prev_hash = 2 [(binary) = true];		// Hash of previous transaction output to spend by this input
+	required bytes prev_hash = 2;		// Hash of previous transaction output to spend by this input
 	required uint32 prev_index = 3;			// Index of previous output to spend
-	optional bytes script_sig = 4 [(binary) = true];	// Script signature
+	optional bytes script_sig = 4;	// Script signature
 	optional uint32 sequence = 5 [default=0xffffffff];
 }
 
 message TxOutputType {
-	optional bytes address = 1;				// Target bitcoin address in base58 encoding
+	optional string address = 1;				// Target bitcoin address in base58 encoding
 	repeated uint32 address_n = 2;			// Has higher priority than "address".
 	required uint64 amount = 3;				// Amount to send in satoshis
 	required ScriptType script_type = 4;	// Select output script type
-	repeated bytes script_args = 5 [(binary) = true];	// Provide additional parameters for the script (its script-depended)
+	repeated bytes script_args = 5;	// Provide additional parameters for the script (its script-depended)
 }
 
 // Transaction output with script pubkey in binary form.
@@ -99,7 +95,7 @@ message TxOutputType {
 // and for compiling TxOutput for signing.
 message TxOutputBinType {
 	required uint64 amount = 1;
-	required bytes script_pubkey = 2 [(binary) = true];
+	required bytes script_pubkey = 2;
 }
 
 message TransactionType {